VQ engine swaps- a royal PITA?

Discuss topics related to the VQ series engine.
dmuramoto
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Classified ads on several Nissan websites are beginning to offer engines like the VQ35HR or the latest VQ37VHR for sale. For late model Z or G owners looking to upgrade, it looks like a fair bargain. Other Nissan model owners are also showing interest as well--hey, I can stuff that V-6 into my S13/14/15 and do a little work to make it run, right? You get the engine, the main harness and an ECM to plug into. Should be a pretty easy swap, no?

In a word, NO. The differences from the VQ35DE to any of the later models is much bigger than you might imagine. Outside of any mechanical changes, it's the immense sophistication of the electronic systems of these cars that create the biggest problems. In just the span of a few years, Nissan engineers have created multi-functioning and interdependent systems running complex software to make the cars quicker and more efficient.

Recently, I talked with a reader who called to ask for advice on a VQ35HR swap into an older 350Z. After going through the list of parts he'd need to complete the swap, he realized how many he was missing. Then, after discussing the kind of expertise he'd need to integrate the systems into his Z, he started to realize how deep the water was. The days of "simple" Nissan engine swaps with this latest generation of powerplants are no more.

For project T2 350Z, we swapped a VQ35HR into a '06 Z33 race chassis. Allen Cox, ASE Master and Nissan Senior tech, took on the immense challenge of charting and repinning the main harness, so we could plug the HR motor into the car without having to swap out the BCM and ABS harnesses and computers. It worked!

But that's for a racecar, not a DD where you're having to put up with CELs constantly lighting up. Some have gone to standalone engine management systems, but even they have limitations. Unless you have extensive experience programming them, it's hard to get the engines to run properly. Worse yet, how do you get all the systems like the new VVEL design to function at all?

By the end of our conversation, I told the reader that he'd thank me later for not sending him down that briar patch. I know. I still have more than a few stickers left in my hide! There's already been a few Nissan enthusists who've cut their harnesses, or found their fully functioning motors don't work any more. Don't join their ranks. We have a few pro techs and enthusiasts on this board and I wonder what their (or your) thoughts are?


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SteveTheTech
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This is a very interesting idea and I know I have thought about this several times. Creating hybrids used to be the main way to get rid of a potentially damaged or outdated drivetrain. When a true Nissan enthusiast is fortunate enough to drive anything with a 3.7VHR the wheels will start turning. I wanted to shove one of these into an old 240, or even my J30.

Sourcing the parts is getting easier and easier these days as these cars are making their ways to the scrap yards throughout this country. However there are far more cons than pros when you get to the nitty gritty. I have had the "pleasure" of performing advanced level electrical diagnostics on these cars and I would not wish that on my worst enemy.

Before seriously contemplating this any enthusiast needs to take into account emission. Although tailpipe emissions might (depending on further modifications) be lower than the 3.5 or older models. The ECM on all 2005+ Nissan and Infiniti models need to initiated and pre programmed before the Nats system can even be programmed.

As I am sure Mr. Cox did some head scratching after all the physical work was done comes the actual hard work. Gone are the good old days when power supply and ground were really the only signals that an engine needed to run. Todays harnesses will not work correctly if there is more than one modification in the entire length of wire. The LAN communication needed between the throttle motors and Accelerator Pedal Position sensor (also might need to be updated) cannot be compromised at all to operate consistently. Also fault detection in circuits like the fuel pump and level circuit can cause CEL that in them selves would cause a car to fail an obdII compliance based emissions test due to not only the variance between the programmed VIN number.

I live in Virginia which has one of the strictest emissions standards and one of the first things that the scanner looks for once the interface is established is the VIN number of the testing vehicle. Although I have never tried I am not completely sure that all ECMs (05+) can be swapped and reformatted to accept a new vin number. If you manage to clear that hurdle depending on what model the new drivetrain is being installed in you may have to simulate several security signals.

Did you need to install the IPDM from the salvaged vehicle? Although you guys were primarily updating a VQ so despite the challenges the fit should have been similar. Although I can only imagine Nissan would do something to make it much more difficult than it should be.

Making the harness must have been fun, well at least that is what I would consider fun. However trying to keep any kind of deadline would be laughable. Although if you guys have any problems and need any help I'd love to help.

dmuramoto
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Steve- thanks for the intelligent and well presented reply. I've sent off a link to Mr. Cox, so hopefully he can answer as well. Your comment of "... head scratching after all the physical work was done comes the actual hard work" is so right on! Allen mentioned this more than once as we were performing the swap this past summer. There were days I saw smoke coming out of his ears as his own personal supercomputer was working out all the variables!

One question I have for you regards a programming issue with the ECM for the HR. It received a reflash from a well-known west coast tuner that delivered less than optimum results. I'd like to get it reflashed back to stock HR specs. But my local dealer contacts say there are no updates available for the VQ35HR and therefore, no way to use CONSULT to restore the program. Could there be any Infiniti bulletins out there for the HR?

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Cyclemut
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Hey guys!

We didn't swap out the IPDM. Although after considering the amount of powers and grounds that had to be initiated, I might have considered it. The other issue that we had with performing the IPDM swap is that we took the engine out of a convertible Z, so even that unit would have to have been modified to not see failures with the BCM as far as expecting to see signals for the drop top motors and such.

I found it 'easier' (so to speak) to just initiate all of the extra powers/grounds for the HR ECU than to continue to modify everything else. We were attempting to keep from swapping out the entire body harness.

One thing to consider with this swap is that there is potentially an easier way to go if the HR were to go into an older vehicle.

Experience with Team Xterra Racing has gained the knowledge that there is at least one company (a shop in Salt Lake City, Utah) that is capable of taking the NATS system out of an ECU while leaving the rest of the ECU alone. Of course, the modifications were for an off road vehicle only, so keep that in mind. I'm thinking that they could also lose the emissions portion of the system, with regards to looking for evap pressure sensors and such. I'm thinking these things could be swapped into an older vehicle, but as long as the emissions of the newer engine are met, I'm of the assumption (at least here in Colorado) that the vehicle would pass inspection. That is, if all the cats were in place, feedback systems intact (wideband O2 sensors and after-cat O2 sensors) and the emissions actually emitted were within the year/model of original HR placement (i.e., 2007 350Z), you'd be good to go.

If, and it's a big if, the shop could remove NATS, CAN and the vapor emissions systems, then a person could have a solid go at it.

After all, they did that with an early 350Z motor in a Datsun on Monster Garage. So it should work, right? :D

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SteveTheTech
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I have thought about this for a while and it seems like there are just so many road blocks that would have to be overcome and trying to plan for and resolve issues before they pop up. If there were a computer program out there that could take to two complete electrical systems and not only find the differences but find a suitable solution this challenge would be about 50% less work. That would still leave the leg work.

One of the first mods I have done like this was in my old D21 pickup. I put the Xtrerra silver gauges in and made it all work. It took longer to find the part number for the male terminals for the combination meter than it did to de wire the old and retrofit it. There was some issues when it came down to the slightly different resistance value causing erroneous fuel level reading. Which if you are like me will be something you shake off until it sputters to death while you are on a date.

When it comes to a reflash for the VQ you guys have I would need to know what the ECMs internal part number is in order to search the database. However I have never tried to undo a software re write. I do not know if the company you used uses a renamed software file. If that does not match what the consult is trying to replace it will not initiate programming. However this should be able to over come with the aftermarket companies software. They should have the base line data stored, or at least that would make sense just in case. Plus in order to establish a baseline they would need the base.

Simple things like exhaust valve timing on the HR motors can cause noises and poor performance that most people will never be able to find as it only happens under load. This for some reason will not set a code on the 05-early07 models but can cause issues.

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Cyclemut
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I think that you may be over-thinking it a bit Steve.

Attempting to undo a rewrite of the software and looking at the exhaust cam timing is more than what's necessary.

And the file name is different for the aftermarket software. It also does not keep the VIN intact. Most rewrites lose the VIN as they use a generic program with certain perameters that have been massaged to afford more power those 1%'ers want.

If getting rid of the NATS software, vapor emissions program and defeating the other inputs that aren't necessary is possible, then these engines will lend themselves nicely to being installed into older vehicles.

Our particular application was difficult as we had to follow the rules applicable to our class of racing. Updating and back-dating the vehicle's powertrain and still keeping within the rules has proven difficult at best. With everything having to remain stock (but still be within the realm of the same series chassis) the task was going to be difficult even if the computer could have been modified to our liking.

With that said, shoving this engine in an older Z, a D21 (that would be my choice!) or anything that could take the weight would be just as much work as shoving in a SuperCharged VG33. Only powerful.

If I had another one of these engines, computer and harness, I'd try it again, in a different vehicle. I wouldn't have to worry about keeping everything stock.

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SteveTheTech
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I have to respectfully disagree. The Xterra is like the Jeep of Nissan where the VG33 can be run in anything and has been used throughout the world for decades almost unchanged. To get a modern VQ to even fire up you need to meet all of the requirements in the below link (page EC-23 is a good starting point). The coil on plug style ignition and no EGR valve are basic differences, when you dig a little deeper you will find that instead of Zirconia tipped O2 sensors the X had the G/Z uses an exponentially more efficient digital air/fuel ratio sensor.

(2007 VQ35HR Engine Control pdf )

In addition to that the old VG33 used a cable where as the VQ (=>3.5L) use at least 2 accelerator pedal sensors and at least 1 electronic throttle body. Not only do all of these devices need to be perfectly set but the wires that connect everything need to be perfect. The VG used old technology even with the SC model (take no offense I personally like the simplicity) but for the sake of argument are decades apart technology wise.

Defeating Nats from a 2002 is nothing like attempting to do that with a 2007+ Nissan, forget bypassing anything with a keyless ignition. Having to replicate the sensors and coded signals even required to energize the fuel pump on a G37 would cost almost as much as the block itself.

Hybrids for anything close to legal daily driving are all but impossible now. Creating things like cable driven throttles and alter air fuel management software (to remove the 0.75% cycling rate maximum for catalyst efficiency) and alter the injector control.

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Don't know about anyone else, but I'm finding this discussion wildly entertaining. I don't pretend to know any of these systems with the kind of detail being explored here, but it's notable that both Steve and Allen (educated and experienced techs with specific Nissan training) have a tough time making things function properly when even the simplest of swaps are attempted. I particularly liked Steve's story of swapping in a set of OEM gauges from an Xterra to his truck. When your D21 sputtered to a halt (on a dark lane overlooking a lake, hopefully), I hope your date accepted the lame excuse that it was all due to differing resistance values causing incorrect fuel gauge readings.

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SteveTheTech
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My date didn't go so well, although I did marry her about two years after that. I wish I could have broken down on a deserted road where I could have worked my mechanic game. No, I was actually on the access road that goes directly by the Pentagon and actually connects two major highways in the DC area and requires you to drive through the actual parking lot the government employees use. That was an interesting experience that involved ruining a very nice Pentagon police officers' dinner and calling AAA and freaking out, and pleading to get me away from the Pentagon as soon as possible. Ahh this area is fun sometimes, but the arrived in 35 minutes which for AAA is amazingly fast. In any case that blew my reservations at a restaurant I had no business being in at that age and it might have actually been more beneficial in retrospect.

Back to the topic at hand.When it comes to creating a Frankenstien cars, older older trucks, Zs and 240s yield themselves quiet nicely all types of options. However over the last 7 years Nissan has been using a very complex LAN network that functions like and other Local Area Network on a smaller scale. Although scoffed at by some of the older generation guys the cars with drive-by-wire are far too complex to modify but that is not actually the case.

If you look through the G and Z forums you will see that modification is possible. Although more difficult to design once you have a way to get into the software and alter the algorithms you can achieve maximum performance instead of middle of the road performance balanced with economy. However many of these software modification use a general programming format nothing specific to the marque. There are tons of products on the market to tune and monitor the software on these cars but they use the OBD II protocal to access the computer but the Nissan computer has a CAN converter that provides real time data unlike any generic scan tool on the market.

Nissan is all about intellectual property and that more than anything has quashed the aftermarket potential. Maybe when the competitions technology matches what we are using they will ease up on their software keys. However if anyone where to get the contract for legit upgrades it would be Impul as they already have ecu and throttle replacements available for a price. It makes perfect sense that these would be pricey but they work.

I have had some experiece with a JWT equipped V35 sedan and the power band was completely altered but in order to do that several parameters will need to be adjusted. Bear in mind that every action has a greater than or equal to reaction. None of the replacement options offer anything close to a DOT certification and still cost more than a factory one. One the reason Nissan themselves is reluctant to get into the market of legit tuning is the DOT certification process for engine control alteration involving crucial software programming there are emissions tests that must be performed to ensure compliance and the company applying needs to pay for all the testing. fast forward a few hours and 3 Aleve, and two beer later I still cannot find the rules that govern this exact topic, I need to let it go for now

This is indeed a great conversation. I really like to debate these types of topics and could do so all day. But for today at least I am done Googling government agencies and various combinations of emissions testing. I am going to look at funny pictures of stuff and go brine my turkey. Take care.

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Great topic and discussion

For a backyard mechanic to swap a newer VQ in, wouldn't it simply be easier to replace about the whole wiring harness with the new, including all the systems? That would require faking out the ECU and such in regards to ABS/VDC, etc. but you probably would not care about those codes registering anyway if it's a classic without those systems.

I'm sure that's just to simplistic. Drop in the VQ, custom fab an intake and throw on a blower with a 4bl carb

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I agree there are ways to make these engines work on their own. Getting the basics covered would be simple (within reason) to get the engine to run with no concern to rationality dtcs or emissions laws. I have seen people retrofit cable throttles to these, why not take it a step further and add a vacuum distributor or a set of points. Cam advancement would only require the signal to be sent to the linear solenoid, spark and ignition timing seem like they would be more of a challenge.

If you lived more nearby we'd have to get together and see if we can crack these open without committing international fraud. That would be fun in my book, the older I get the less heavy lifting I want to do and more computery geeky crap I prefer. huh interesting.

Hey Matt- the link from nicoforums recent topics ( zer...opics ) with a NS thread always goes to this link ( http://www.cnwzcommerce.com/mm...37469 )

So as usual I have very little going on and I was translating the impul website and it appears that even on a Cube real performance starts are 2 grand and a 5.1 block for a Y50 M45 costs in excess of $20,000 plus shipping. Oh and none of their stuff is clear for sale in this country but it makes me drool and many other Nissan enthusiasts will realize just how far ahead of us the Japanese are.

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Yep, I have seen some retrofit larger throttle bodies on the 5.5-gen Maxima which required a throttle cable retrofit. There is a large "fly over" area in the US where there are no emission laws as well so I'm sure some of these conversions will take place.

Yeah, I'm aware of the problem on the NICO forums. It's because Nissan Sport Mag has not rebuilt their site after the cyber attack and their sub-domain setting for this forum is gone

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audtatious wrote:Yeah, I'm aware of the problem on the NICO forums. It's because Nissan Sport Mag has not rebuilt their site after the cyber attack and their sub-domain setting for this forum is gone
Our apologizes. Our website was badly hacked to the point of being unrecoverable. The staff has been busy getting the next issue out, so we haven't had the time, money or effort committed to rebuilding the Nissan Sport website yet. But we plan on doing so.

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SteveTheTech
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Sorry to salt old wounds I was unsure one whos end it was on. In either case this site works pretty well for the most part. It's still my favorite site.

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No worries, Steve. It's appropos for this discussion that our hacked website could affect a discussion board here at NICO.

Back to the discussion- you mentioned how much more complex the Nissan LAN systems have become over the past seven years, but I think the last three years have become exponentially more sophisticated. As we found out with Project T2, the VQ35HR has more data points being collected than the older DEs. Worse yet, the FSM for both the '06 and '07 models showed only a limited amount of information on pin-outs so Alan could re-wire accurately.

To gain more info, I called upon some of my contacts at Nissan and was told the Nissan Technical center (NTC) and another pro race team had done the HR swap into Z33 chassis. The pro team I knew and contacted. But the info was incorrect- they did not complete or even attempt an HR swap and wanted to know how we did it! The NTC team did what Audtatious suggested and swapped main and body harnesses, along with BCS and ABS units. They still had CELs and other problems with their engineering mule and that was with full factory support...

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dmuramoto wrote:
Our apologizes. Our website was badly hacked to the point of being unrecoverable. The staff has been busy getting the next issue out, so we haven't had the time, money or effort committed to rebuilding the Nissan Sport website yet. But we plan on doing so.
Absolutely aware. I need to hit Dave up to see if the foums.nissansportmag.com sub-domain can simply be relinked to this forum. That would take care of any domain issues.

Now, back on topic.

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I had a long held idea that the guys in the factory technical jobs would all be gung ho about the new products usually are more big corporate guys than actual car guys. Although I am not sure how that sounds to others but everyone I have met has been has always been perfectly nice, which does not always get the problems resolved.

The kind of technical hurdles that would be faced to design either a harness for this or ecm that would work in the swap would almost always have to be custom made and would involve some serious R&D. If I were to leave my current position I would love to tackle problems like this but there is such a small market for this that it seems highly unlikely.

The network in these cars is exceptionally fast but in order for anything to operate, it uses the classic twisted wire type comm circuit. How this will complicate the future of hybrid (new motor-old car) is the initial verification that all CAN networked control unit to monitor power supply and ground down to the microvolt and microsecond second range and logs a fault. Unlike common OBDII logic there is no two trip detection in some of the systems and depending on which level of fault is logged the system may immediately go into failsafe mode. So technically if you are not using the combination meter that the original car had might alter the speed signal input to the ecm causing potential issues. There are stupid things like the ground signal for the fuel level sensor that runs through the combination meter and to the ecm for circuit integrity confirmation.

There are little things in these cars that are required to run legally in this country. However if you were to set something up purely for race (and money was no option) you could create an ecm and basics harness that would take the basic inputs and make a decision instead of relying on legal stuff. This would make sense why the impul kits are as pricey as they are. If someone had the knowledge to either bypass or integrate the can functions into a performance oriented mapping instead of the usual adjustments of timing and the typical things available for some of the modern Nissan offerings.

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Steve's read on factory assistance is an interesting side topic. My experience has been much the same, with both polite and professional replies to engineering questions, but no real answers. I've been told that some of the engineering data I've requested can only be answered out of Japan, which may be true. But it also seems that Nissan personnel are well indoctrinated to knowing how much they can divulge (which isn't much).

It's enough to make me wonder if it's an overt strategy to squeeze out the aftermarket. Even if it's just a side benefit, the fact is that it's getting harder and harder to modify these complex OEM systems on a basic level.

As for race applications, certainly standalone ECMs or aftermarket units like Impul are options, depending on what the rules package is. I only wish money were not a limit for the SCCA T2 rules package I work with! But it's a good illustration of the roadblocks you run into when using the stock LAN and ECM housing. Enhancements to programming can be considerable when you have factory assistance, as shown by the Solstice GXP when GM decided to race it. They had factory engineers at the racetrack performing software adjustments for several years. Even though all those resources have disappeared, these turbo cars continue to perform well. That advantage gets magnified if you race at altitude against those ex-factory cars most of the year.

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It kind of rubs me the wrong way when the factory guys come in and fix stuff with the attitude that they are doing our job for us. Well this is really only half true, they are privy to information the majority of us techs will never see. The primary reasoning for this in my honest opinion is the Hyundai Genesis. The coupe is too similar to the G for my liking and the sedan from the front looks like a cheap S class.

Some say flattery is the best compliment but when it comes to cars it is business. Looking at the two the untrained eye will skip the quality variance between these models and they still have the cheap looking digital clock that they have had since the mid 90s. From a numbers only perspective they are cheaper, have a better warranty, and some have better performance numbers. However where we beat them is actually creating the technology not just borrowing from others. They lack the refinement is typical of the knockoffs. Hyundai hasn't had an original thought since the Accent from the 80s that had the master cylinder on the passenger side of the firewall connected by a rod.

Technology like VVEL and specifics on their CAN technology will benefit a minuscule amount of the service staff but mean more to competitive companies. We have the first run of much of this technology and future models will take aim at the industry itself.

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Steve- your comment on factory reps coming in to fix "your" stuff has been around for quite awhile. But I think the trend is accelerating with the increasingly complex technology that Infiniti/Nissan is seeking to protect. There's little doubt they are in the crosshairs of quite a few rivals as the quality and sophistication of Infiniti vehicles continue to set new standards.

Interestingly enough, I had the opportunity last spring to attend the Genesis Coupe introduction and see how Hyundai handled it. For the most part, the launch was good, but lacked the refinement that Infiniti puts into each of their events. Same for the product, as I had the opportunity to drive the V-6 and turbo 4 cylinder Genesis Coupes around Spring Mountain Motorsports Ranch at speed.

As you say, the cars are not in the same league as the G37 Coupe, but for a first attempt at a true RWD sport coupe, it wasn't bad. Refinement and sophistication are not the strong points for that product, but I think the Korean company and their US affiliate are on the right track. Competition in this segment continues to rise and the technology, quality and inspired styling will keep Infiniti out front. Still, that doesn't help us "car guys" as we seek to understand and build improvements into our projects.

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Well, I kind of forgot about this thread until David reminded that it was still going.

These things aren't that complicated. There's no super-secret password or handshake that makes these things work.

If you have a donor car, you have everything you need! Accel pedal assembly, bolt it in, run the wires. As long as the resistance for the circuit is within parameters, you're set. This computer is pretty resilient. If the circuits are good, they're good. It will run, not just good, but normally.

There seems to be a tendency to do over-think this stuff.

I'm not some guru. I'm not a magician.

Running the same gas pedal with the same harness connected to the same ECU will yield the same results. Lengthening the wires (soldering, not butt connectors) will still let everything work. Making the CAN system work isn't anything different. I've repaired the CAN system using the same technique.

Talk to any Nissan Engineer and their face will just about turn white if you tell them that you soldered a CAN wire splice in to make the system function again. I've done the same thing on SRS wiring. Oh yeah, the sacred 'yellow harness'. Don't touch that one, or a kitten will die. BS!

I'm not saying it isn't difficult, I've got experience with custom harnesses, going way back. I'm even building several custom cars similar to the Ariel Atom. But that's another thread.

What I am saying is that if someone has the time, the desire, the basic set of skills to decipher an electrical diagram and has the donor car, then they can swap this engine into anything. You don't have to convert to a throttle cable. You can have the NATS system pulled out, it's been done. You can have the ABS, SRS and TCM inputs all taken out, it's been done. Dakota Digital makes pulse modifiers to trick anything into becoming what ever signal you could need, like a speed sensor.

Really, a donor car makes life so easy, it's not even funny.

Kind of makes things easier if you look at it after a couple of beers.

ETA: I used this manual for the swap, specifically pages 101-102, then all the pages after that, looking at each individual sensor circuit to insure all circuit resistances were within specs for the vehicle that it was going into. Now I have to do the same thing, but backwards, to get the older engine to function normally in the newer vehicle. Not even Nissan has attempted this swap. Hell, they didn't even get the swap we/i] did to function normally.

http://www.nicoclub.com/FSM/350Z/coupe/2007/ec.pdf
Modified by Cyclemut at 7:23 PM 12/8/2009

turbocad6
Posts: 17
Joined: Wed Dec 30, 2009 1:42 pm
Car: 03 fx35

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hey guys, I already frequent & even moderate a few forums, but I joined up here to add to this discussion & to perhaps get a little input & maybe even a little help from you guys. first of all I am(or at least was) a technician & I have done my fair share of engine swaps in the past. I was the guy to go to back in the day when no one else could figure out the wiring & I would love to be able to take a big tangled ball of spaghetti wiring & trace & shoot each circuit down & get everything working. I've seen a lot of things that people have said is impossible or impractical & would love to prove them wrong by doing it. I've retrofitted complete digital climate control systems & digital dash swaps & engine swaps in the past, more than a few grand national engine swaps & a few lt-1's, stuff like that.

back in the day when fuel injection first started hitting the main stream in the us market many mechanics were intimidated by it, & I have known more than several that would condemn that new fangled fuel injection crap because they just didn't understand it, these were the same guys who were ripping the fuel injection out & putting a carburetor in it's place, or ripping out a feedback type carburetor with the MC solenoids to replace it with a non computerized version, while I was the type of guy to want to rip out a carburetor & install fuel injection. I think today is similar in that many don't fully understand the can buss & therefore don't think it can be delt with for a swap like this.

well, I now own a body shop so I've been kinda out of the loop past 15 years or so, & while I do know a bit about obdII & can communications buss, it's no longer something that I do day in & day out. also I haven't been keeping up with the latest by going to school anymore either, so I can't really say that I'm a true top level tech anymore as the latest technology has advanced quite a bit in the past 15 years, but, I do still dabble from time to time & I do still have a firm foundation in electrical knowledge from my past.

anyway, I now have an fx35 that has a very tired 3.5de engine & I did a bit of research & I have decided that I want to do an HR swap in the fx. I bought a motor & tranny from a g35x, complete with the front diff, harness & ecu & prepping it now to drop in. my thoughts are that there are 3 possible ways for me to do this as far as the wiring & getting it running.

first & preferred way would be to get it running on the HR box, which so far is my main goal & target. my thoughts are that the can communication buss that communicates from the different modules can be connected to the 07 ecu & that chances are pretty good that the 03 components will more than likely still communicate with the 07 ecu for the most part. the can buss is nothing more than just 2 wires, can high & can low, & all the modules are connected to each other through this buss. each component sends packets & sniffs for packets made for itself, just passing on the packets that are not useful to the next module in the daisy chain & I think the chances are pretty high that the language & packet specs on the 03 stuff is going to be the same as the 07, I'm hoping that for example the 03 IP module is sending out & receiving the same basic data that the 07 might have, same for the body computer & hopefully even the security module or the NATS, the cruise module etc...

now where I'm getting a bit concerned is, even if all of this is true, I still will need some external help. for example, even if I get it in & fully wired up & everything is a go, I'd still need someone with a consult III to be able to reprogram the keys to the HR ecu before it could have any hope of even starting because of the NATS system. of course after the fact I could indeed realize that there may be communication differences elsewere too, would I need to swap out to a 07g35x body computer?... is it possible that the IP module is different enough that I need to source even more g35x components? the adaptive cruise, the ABS, stuff like that. even though I'm thinking that the communication protocols & the language is probably all the same or similar enough that most things will still function I of course have no way of knowing for sure until after the fact.

second option I see is to drop the HR motor in, but then run it off the existing DE ecu combined with a Utec. I believe this is a more sure fire way of doing this, as I'm fairly sure that I can get the DE ecu to run the HR motor. this would involve me having to build a custom intake though & going back to a single TB setup instead of the dual TB of the hr. the only other issue would be the exhaust valve timing control which of course the DE knows nothing about, but, from my research too I'm lead to believe that since the exhaust valve solenoid is very simplistic & basically either on or off & rpm based, this control may be doable with the utec that I already have now on the DE ecu.

third option I see is using a stand alone, only issues I see there is I can't say that I've ever built a car with a stand alone ecu before, & I'm not 100% clear on how something like this is used... I mean I find it hard to believe that a stand alone completely replaces the ecu & completely integrates with the can buss for all functionality, but I'm not so sure about this, is that really the case or does the stand alone still rely on a factory ecu for communication? can a stand alone ecu be used to run the HR & still keep all the 03 fx boxes happy at the same time? I also want to add that I have intension's of turbocharging this HR motor, so with that in mind a stand alone doesn't seem as Far fetched, although I'd love to ideally be able to get it running on the HR box & then Osiris tune that...

anyway, I don't think any of you guys can totally talk me out of dropping this HR into my fx, because I've already decided that I am doing it, & since I've already decided that, that means that I've already decided that I will do whatever it takes too, weather it involves having to source a whole bunch more g35x parts or going stand alone or whatever else it might take, so trying to talk me out of this is not really what I'm looking for here, I'm more looking for any other helpful info or input anyone may have to offer. also, I am glad to have found the ecu wiring & data here, but I was wondering if anyone else happened to have the body portion of the fsm, particularly the part that contains the NATS wiring, so I can compare stuff to the fx FSM. I also seen someone mention that there was a way to remove the NATS from the ecu, any further info there would be great. I do realize that most would consider something like this impractical & of course this is the reason it hasn't been casually done before, but I refuse to believe that it is impossible either, & this belief is enough to make me want to do it.

anyway, a bit long for a first post here, but thanks in advance to any help that anyone may care to offer, I did have a pdf FSM for the g35x but I have since lost it & need to search for it again, I'd appreciate anything or any advice or information that anyone has to offer & am glad to have joined your community here.

dmuramoto
Posts: 312
Joined: Mon Mar 16, 2009 5:20 pm
Car: 350Z street, 350Z GT3 and T3 racecars, Versa HB and Infiniti G37xS sedan

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Welcome turbocad6 to both this discussion and the Nissan Sport Magazine discussion board. I read your post with interest and it looks like you're going into this with the right attitude. I've no doubt you can accomplish your HR swap, the only reservation is the amount of time and effort it will take to accomplish your end result.

My HR swap was for a T2 racecar and, while it's emissions compliant, I don't have to register it for the road. To accomplish the same for a registered and licensed FX might be tougher. As Steve the Tech pointed out, different states have different standards but many will penalize you simply for having a CEL appear. I suspect even after the mechanical and electronic sides are buttoned up there'll be any number of electronic glitches that'll show up.

I'll let Allen or Steve comment specifically on the technical questions you pose. They're the genuises here, not I. But it's interesting to note that I started this thread to help Nissan enthusiasts become more aware of the multitude of issues involved in what would seem to be a "simple" engine swap. I've seen guys with minimal mechanical and technical skills consider an engine swap with minimal resources that have only one inevitable conclusion. Their buddies will even egg them on: "dude that would be awesome! We'll do it this weekend in the parking lot of your condo."

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Cyclemut
Posts: 64
Joined: Tue Mar 27, 2007 8:36 am
Car: 2002 Xterra 4x4, 2005 Frontier 4x4

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OK, so I won't talk you out of it. Now that we've got that out of the way, let's move forward.

Your best best, without the turbo, is to use the HR ECU. You will not be able to use the DE computer to accurately run the engine with the Utec without having to constantly tune it.

With the turbo, the HR and another unit will suffice, but not with a ton of boost.

Although I won't talk you out of the swap, perhaps I'd lose the turbos. That's something that could be accomplished after you get it all running. Really, I'd reconsider it.

Now, Nats, you could either have it removed or simply leave it in. I would leave it in. Have the computer reprogrammed to accept the FX key code. It will add to the security of the vehicle and for a street vehicle, you lose nothing by keeping it.

Discussing the Nats before was for putting the engine into a vehicle that Nats wasn't even a pipe dream for or, as in our case, putting it into a race car where a steel key would be best suited.

Can buss, just hook it up. Done.

Next, powers, grounds, power steering module, stop and cruise brake switches, fuel pump, etc.

Doable, yes. But I think you will find more problems with the mechanical stuff than the electrical stuff.

Like, the starter is on the opposite side now. Hope the steering rack clears it. We were lucky and the newer model 350Z donor vehicle bolted right in. Purchasing a newer one, hoping it fits, will be expensive. This will be much more difficult than just bolting an HR into something similar to an old 720 or 510.

You've got some work, it won't be easy, I just hope that it's worth it for you personally in the end. It will undoubtedly be the most expensive FX that I know of.

turbocad6
Posts: 17
Joined: Wed Dec 30, 2009 1:42 pm
Car: 03 fx35

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cyclemut, I typed this following post before seeing your reply, I will respond in the next post, but want to post what I have written so far:

I found my pdf's & have spent some more hours reviewing & learning & studying & comparing, I agree that the emissions control & state inspection is a very big issue & should be a primary concern in dealing with a swap like this, this is not a race car for off road use only & has to be inspect-able to not be a big waste & destroy the worth of the vehicle really.

I have a friend with an inspection station & another who is an investigator for the state dmv and today I have talked to both of them about the ways of getting a valid inspection, in NY if the vehicle does not have a valid inspection the dmv will not even renew a registration. I'm now seeing that the day of just sticking another vehicle on the machine & generating a sticker is no more, an inspection is done with a live connection to the state computer & likes been said, one of the first things that the state equipment does is confirm the Vin #.

initially guys have come up with a method of initiating the inspection on the target vehicle & then switching the cable to an alternate vehicle & successfully completing an inspection, but the newest state software does another Vin check mid way through & this has become very difficult to trick, bottom line is for a swap to be considered successful then the vehicle must be done in such a way that it can legally pass a state inspection through the obdII interface at least. what the state computer don't see doesn't matter so much, the idea is for the ecu to not see any problems & pass with no red flags.

incidentally, the state inspector also tells me that in the case of a Vin not matching the vehicle's pcm stored Vin, the inspection can still go through, but it will raise a red flag in the dmv & they will investigate, they investigate the inspection station mainly & the fines for improperly done state inspections start at $1,000 each, his own words are that they are giving the shops just enough rope to hang themselves because this is a big revenue generator for them, so you better make sure that all required emissions components are in place & nothing else is tampered with or altered in such a way that the vehicle should have failed visually at least to protect the station, but the station will not be penalized just for the fact that the Vin is incorrect if everything else is 100% legit, if the car has a turbo setup or anything else that is not carb certified then you def don't want to kick up any red flags though & need to stay under there radar with a green flag inspection, the NYS dmv is actively searching for situations just like this, also if it detects one Vin on initiation & another midway through the procedure of an inspection the inspection station is going to get screwed for sure

I'm told they are seeing issues pop up here & there with salvage pcm's swapped. he even told me of one of his more recent cases of 2 identical Nissan's that belong to 2 separate owners on either side of town. they got a double red flag because each vehicle had the incorrect Vin # stored in there ecu's... turns out they had each others vin... the investigator eventually traced it down to the local dealer at some point having these vehicles side by side & troubleshooting an issue winded up swapping the ecu's to test, & then for some reason was never swapped back, the tech just thinking it didn't even matter because they were both the same & it wasn't the problem anyway... I only spent about 20 minutes speaking with the state inspector & I didn't have the time to ask him 101 other questions I have, but I will find out more from him next time I speak to him

my goal here is not to try & find a way to circumvent a legal obdII scan inspection, I want to pull off a swap that is legal enough to legitimately pass a state inspection at the obdII interface. my understanding of rules for an engine swap is the new engine must be of the same year as the vehicle or later, & must have all of the emissions components of the later engine in place & functioning & meet all of the requirements of the later engines requirements, at that point it is a legal legitimate swap. I don't want to have to compromise the inspection station in any way either & red flags while I have a set of twins on this thing can be trouble.

I need to find out if my 03 Vin can be entered in the 07 ecu, I've asked a few Nissan techs & have only gotten a few "I don't know but I'll try to find out for you" answers so far. I guess this may also be a question for the aftermarket ecu re flashers too maybe?

if the state computer verifies a correct Vin, & then verifies that the readiness monitors required to be ready are ready, & that there is no check engine light for an emissions related issue & no stored codes for an emissions related problem then the vehicle legally & legitimately passes a state inspection with a green flag at the obdII scan level & were good to go. this must be achieved for this to be a successful swap to me. the vehicle will not fail if the abs doesn't work, or the stability control or the cruise control or even the airbags & the dash is lit up like a Christmas tree, the pass or fail with the state computer hookup is strictly emissions & check engine light Dependant.

turbocad6
Posts: 17
Joined: Wed Dec 30, 2009 1:42 pm
Car: 03 fx35

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from the FSM's there are like 16 different can bus system types, depending on the engine & the options the vehicle has, they are broken down by the options the vehicle has, & mine being a tech package awd vehicle should mesh well with the g35x ecu I have if it was a tech package ecu with Ikey too, which chances are it was. for example my body control module is not set up for a push button ignition, but it is still a proximity sensor Ikey system, & in the end the important part of that is that it will still be able to communicate with the newer ecu & still perform the key coding communication necessary to re-learn the keys, it should work & I would of course rather keep it if it does work, your words are reassuring, I would think it's possible to get something like this done & have all trouble codes solved & everything working 100% if everything communicates, which it should... what kind of codes would you get that can't be solved? maybe for a race car shooting it down enough to satisfy the ecu is not a priority, but I can't imagine a fault that couldn't be corrected really for a street swap

there has been much speculation on the fx forums about converting to a push button ign, swapping the bcm from a push button ign system like the g would be the ideal way to accomplish this, & may be a good enough reason alone to swap out the 07 bcm eventually if I ever get my hands on one with the harness pigtails, wish I had the one from this drive train & the keys even, but initially I will connect it with the existing 03 key & attempt to have it programmed with the 07 bcm. I've already installed a 07 ipm earlier & it communicated no problem & works fine, hopefully everything plays nice with each other

forced induction is the reason for the swap in the first place so you don't have much chance of talking me out of that either really . my fx is my own little modified 4dr 350z with a backpack, I have it lowered & modified I've already been to Pocono raceway with it & plan to do a lot more track time. I have it hanging fine in the twisties & was able to really just about hang with even the m's & some other respectable cars, but once I come around the last turn & to the long straightaway I just fall flat on my face & wind up having to wave everyone by . I want to increase to ~450 to the wheels, not looking to go crazy, but looking to go past the point I'd feel comfortable with on the stock DE motor, I'm looking for ~525 to the flywheel reliably. the hr motor is more than enough for my use, where I'd have to use a built DE instead, I feel more comfortable with a factory assembled low mileage motor than a rebuilt anything from some unknown, & a good reliable built substitute in the DE engine from a reputable builder is maybe triple the cost of this HR motor, & in the end I'd probably still trust the factory engine more tbh

I agree that this swap is probably not worth it in a 350z, I mean even if you had an 03, you could probably just sell it for 11k & get an 07 for like 19k, your not going to save a whole lot by performing this swap & considering that the investment of upgrading to the 07 will also result in a vehicle with a higher resale value it makes this even more of a no brainer, but the fx is different, the HR motor only became available in the 09's... the 09's are a whole different animal, & even if I did want to do the trade up the gap between what I have now & what I'd have to spend for the new one is much wider than the gap with a Z, were talking +25K more to update to the fx with the HR... compare that to my original plan of new HR engine & transmission, complete with FI making 500+ at ~ the 10k mark, can't do that with the dE at all, the HR is the budget bang for the buck way of doing this in my eyes...

I was considering ordering up the beginnings of the turbo components but I have since decided to just not let the turbo's distract me from the main goal right now & will have FI be stage 2 of this project, I'll consider options for the FI depending on how I get this in & running.

I really think it would be pretty simple to get this running on the DE ecu if I'm willing to loose the dual throttle bodies & the variable cam timing, & in the end this is still enough to be worth this swap considering my goals, but of course I'd much rather have it all with the HR ecu...

the mechanical part I'm not so worried about, I'm sure I can fabricate anything & alter whatever need be, that's the least of my concern.

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SteveTheTech
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cyclemut wrote:Talk to any Nissan Engineer and their face will just about turn white if you tell them that you soldered a CAN wire splice in to make the system function again. I've done the same thing on SRS wiring. Oh yeah, the sacred 'yellow harness'. Don't touch that one, or a kitten will die. BS!
They actually say one fix per harness is acceptible as a CYA policy. For this type of custom modification where the person that is doing the work knows the proper procedure to create a connection without compromising the resistance value of the wire. Since there is no base level of skill required to do this type of work things like SRS harness repairs have been discouraged by Nissan while many of the domestics taught their senior techs how to actually diagnose and repair these instead of having people replace the entire harness for things that cannot be found.

There is (or at least should be) another level of skill required to successfully do this type of job. I am glad to see there are people who are interesting in doing this and I thought I was alone for a while. I think we could all learn from each other.
Cyclemut wrote:Can buss, just hook it up. Done.
I actually lol'd loud enough to attract the attention of my wife while reading that and when I told her about it I got a look that I was lying and doing something inappropriate. lol

Turbocad6- Welcome to our discussion and this forum, what type of forum are you common on?

It would be really easy if you could just swap the motors and it would just plug in. However everything from the heads up is going to mount differently.

As far as NATS goes I don't know how much of that we can/should really get into in a public forum. But there are some vital differences between the 03 FX and the 07+ G mainly including the ikey system and basics of control are very different. However if you can replicate the start signal to the ipdm you would be in business, however that in and of itself is going to only be able to be done with trial an error. To anyone who has attempted a CAN diagnosis since they came out in engine control in 2002 you will know that for each model there is at least one can type for every major option. Those of you Nissan guys will remember the 03 Murano had >30 CAN types all requiring different things to meet the basic needs and work correctly. Crossing 4 model years does not seem like the largest feat ever attempted but the VQ underwent some serious changes over that time span.

The proximity detection of the older ikey is mechanically very similar to the newer system but I think the components used are very different. This will be the first and one of the larges hurdles you will have to conquer before you will be able to see what all else needs to be done to get the lights on the dash to come on and the initial sensor checks to be performed to get the all clear to the ecm. Even on the same year some of the same models there are several options for keys so the huge brick key from the first fx might not work.

The push button start from the new G sounds like an easier addition but the sensitivity of the new style steering lock control unit and new key registration procedure will require some magic and a serious time commitment.

I do like you drive though where you would like to get the icc from the new G up and running. That is a good idea but I think for that you will need at least the bcm and the entirety of the body harness. Allen is completely right on with his comments about a donor car. It would take at least one complete G and maybe more parts off of an fx.

Your best bet might be to try a remote start to replicate the start signal for the short term but that sometimes fails to meet the needs of the security system. If you sit in a new G and crank it up you start by putting your foot on the brake and press the button. Within a split second the ikey control unit verifies the ikey id and sends the signal to proceed to the ON position. There are a few verification checks that need to be seen before the start signal can be given.

As for needing the Consult III this is indeed the case, however you might have a serious problem for which I cannot think of a way around. What are the laws in your state regarding emissions. I know in Virginia when the emissions test is run the VIN number is read by the computer. I really have no idea if you will be able to install a VIN that the car will not register. If there is an anomaly like that I know our emissions machine stops right there and rejects the car. Maybe you can apply for custom plates or special purpose plates but you really need to look into that before you start investing the money...well more than you have.

Now if you are building this for show/fun more than a daily driver that is one thing but at some point you would be better off getting into a new fx and having this already done with a much nicer interior.

Building a race care and building a daily driver are two completely different creations. I think the amount of stress of the daily driver project will cause premature gray hairs. Good Luck with this it sounds interesting.

If I were to consider doing this I would look seriously running with an Impul kit and a low mile new DE motor. Hell a VK swap would be easier than what is being proposed here.

turbocad6
Posts: 17
Joined: Wed Dec 30, 2009 1:42 pm
Car: 03 fx35

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I'm on mp3car.com for quite a few years now & one of the things I find very unique about the mp3car community in general is the amount of people there that are willing to unselfishly share information with each other & help each other & go out of there way to help others. the community is built of everything from computer programmers to electrical engineers & of course a whole bunch of other enthusiasts from any & every field. there are many projects that are a collaboration, formed by many members of the community to benefit everyone & there are a lot of awesome community developed products & projects that result from it, most are freely shared in the interest of sharing & giving back to the community, sometimes a project that would otherwise be impossible can become possible with the pooling of information & resources. I agree that the more information that is gathered & then shared about a can buss swap the better it can be for anyone else also looking to travel down the same path in the future. I'm surprised there isn't all that much info anywhere about the topic of can buss engine swaps. I'm also on infinitiscene.com which is a relatively smaller mainly FX forum that is very dedicated to modifications & just a general appreciation & love of the FX.

as far as the topic at hand here, there is just about no real information out there, just a whole bunch of people proposing the same questions & then a whole bunch of responses that it is too difficult & just not worth it, too many unknowns & too many potential problems but in the end very few even have a real clue. I haven't been able to find one intelligent conversation anywhere that was any kind of helpful at all, well, except for this one. this was the only place that I could find anything really helpful & being discussed by people with more than just a clue of what's really involved.

I agree that having a complete donor vehicle is the ideal way to have everything you need, but this is not always practical or possible & not necissarily manditory for this either. it's easy to just take everything as a whole & drop it into an old body & get it to work, one guy is doing one & even using the 350z dash & all from the donor car, but I think it can be grafted into an existing car that already has all systems in place too & may even be cleaner & easier than swapping out whole dash harnesses.

ok, Nissan's NATS system is designed in such a way that the BCM is paired to the Ikey for the vehicle's actual ign lock mechanism, the bcm controls the whole show as a wireless ign lock all by itself, but if Nissan just left it at that, then anyone would be able to swap out the BCM with a new key programmed to the new BCM & be able to drive the vehicle away, the NATS system simply expands on this by also requiring the BCM to transmit it's learned key code each time a start is attempted, & requires the code to also match the ecu stored code, that's it in a nutshell really. if the NATS was removed from the ECU then the electronic ignition lock would still function fine with just the BCM, but this would be a security vulnerability in that anyone would be able to start the vehicle with a new BCM/Ikey combo. of course if all Nissan's were set up this way it would be a huge vulnerability, but if just one vehicle happened to have the NATS removed from it's BCM who would even be the wiser? what are the chances someone is going to steal your car by breaking in & replacing the bcm with one that they brought with them & had a key programmed to it? especially since of course this would never work on any other Nissan/infiniti, I don't see that as a big problem if it had to be lost but I will keep it if possible of course which it should be.

the BCM itself does all of the transmitting & receiving with the key for confirmation to allow the electronic unlocking of the ignition, now granted the 03 system is very different from the 07, but in the end it shouldn't really matter, I mean the 03 BCM will still control the existing 03 ign lock equipment, & should still transmit the key code to the ECU through the can buss with the correct PID's, first time for programming & then each start same thing, allowing the ECU to send a start signal to the IPDM. if I had to swap out the 07 BCM then of course I would have to swap out the rest of the components that the 07 BCM uses for it's ign lock architecture, the button & maybe the later lock assy & also including of course a latter oval shaped key (another good reason for a BCM swap even if not necessary otherwise) but I really think the 03 should work the same & will send a key code to the ECU that it can in turn learn & work the same as it would otherwise & retain the NATS functionality.

the Nissan control system works in such a way that each individual system is primarily a stand alone control for the system at hand, be it the ABS or the BCM with the IPDM as the common module used by the others for the higher amperage switching & power distribution chores. of course these individual systems also rely on communication with any other module on the buss that it may need to communicate with through the can buss, both transmit & receive.

all of the systems that are in place & fully functional right now will still all be in place & have the same potential to continue to work as they do. they will still send the data over the buss that is addressed to the ECU as it always has & the new ECU should be able to recognize this data & send data out that the respective modules addressed to should be able to recognize & respond appropriately. the data sent over this buss is sent in packets called PID's. each PID is a specific bit of data & every PID initiates with an identifier that allows each module that it passes to know if this PID is addressed to itself or not. where potential problems would come in is if:

A, the new ECU receives a PID that is addressed to itself but it doesn't recognize the data(unknown result)B,the new ECU sends out a PID that it needs a specific response for, but doesn't receive it(unknown result)C,one of the existing 03 modules receives a PID addressed to it from the ECU but the module doesn't recognize the data(unknown result)

chances of any of these situations happening may be Dependant on if the newer system happened to use something that the older systems are not aware of?. also probably somewhat Dependant on the can buss system type, which is basically a matter of the options packages on the vehicles being compatible with the options packages of the ecu. try to use a rwd non tech ecu in a tech awd vehicle then of course your going to have problems with stability control & many trouble codes with improper communications, it's not that the actual PID data is any different for any specific can buss types though, they are all speaking the same language really, it's a matter of recognizing & expecting what it is receiving & getting the expected results from the data it sends. the different can buss types identified are only for trouble shooting purposes so they can just go through a tree appropriate to the systems in the particular vehicle, so if there are 30 different can buss types then that means there are 30 different trouble shooting paths that can be gone down depending on the systems installed.

while there are potentials for communications problems, for the most part I bet that everything will play nicely & the main functionality of all systems should be able to be retained as long as the ecu is from a vehicle that had the same options. now to be able to program the 03 vin into the 07 ecu, that's the first hurdle that needs to be overcome. I'm thinking this shouldn't be so difficult, I'd be a little surprised if it can't be done...

turbocad6
Posts: 17
Joined: Wed Dec 30, 2009 1:42 pm
Car: 03 fx35

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adding to the above I see that I left out another possibility in that list of A,B & C, which would be D, & that is a situation that one of the sub systems needs a PID that would be generated by the original ECU but the new ECU doesn't send it.

OK, a little more research to the Vin of my donor drivetrain reveals that the vehicle my ecu came from did indeed have Ikey, but it did not have radar cruise or navigation. now I know of course how the radar cruise would interact with the ecu, but I don't realize why the navigation needs to communicate with the ecu, although I believe it does. I'm assuming that if the radar cruise module was not connected to the can buss then the ECU wouldn't even see it or care & would function as if that option was not installed, but then of course that system itself won't function either...

I have read in the service manual that the ecu will report an error if it doesn't see can communication with any of it's systems for .5 seconds or longer, BUT that the ecu will ignore these errors if the system is an optional system. does this mean that the functionality is in the ecu even if that particular system is not installed in the vehicle? is it possible that even though my ECU is from a vehicle without radar cruise, that if it does wind up seeing communication with the radar cruise module that it will react & work with it anyway? I'm betting this is a long shot, but not impossible... if not what are the chances of getting a re flash to a program from a vehicle that does have the radar & nav?... maybe need to source an ECU from a vehicle that had these options? maybe the answer is a new blank ECU & then have the options coded & the correct Vin learned?... so many questions that have no answers yet...

User avatar
Cyclemut
Posts: 64
Joined: Tue Mar 27, 2007 8:36 am
Car: 2002 Xterra 4x4, 2005 Frontier 4x4

Post

OK, you two guys, wow.

It's not that complicated. The NATS system only wants to see a key code that it recognizes. If the ECU puts out the signal on the CAN system that it's good to go, the BCM will do it's thing and unlock the doors the way the FX wants it to. If the ECU sees that NATS is good to go and then start the engine.

The CAN system is a twisted pair of two wires. It's the same color all the way through the vehicle. When you cut the harness at the vehicle's ECU connector (and you will have to), you will see those two wires. Guess where they go? To the ECU. The exact same thing you're splicing into the vehicle from the donor vehicle. Hook them up. They're the same color from the donor vehicle's harness.

One thing that I can say, for a fact, that you are currently running into. You are overthinking this. Waaaaaayyyyyy overthinking this.

Most everything can be done easily, with just a little attention to the details. You have the harness connector pinout for the donor vehicle. You have the all the powers and grounds listed right there.

One thing I would suggest is to run a big power wire closer to the ECU for the powers and then a big ground that you could connect the other grounds to that are necessary for the new system.

I have done the swap into an older vehicle. The mechanical part took us longer than the wiring. After that, I just took my time. Since we were the first, we ran into some issues but they turned out to be simple little things that were caused by our comm system with the vehicle, not the wiring itself. After working it out with UpRev, we were all set.

Just match the wires up. Some change color, so you have some tracing to do, but with the FSM's in hand, you'll do great.

I don't know what else was said, I'm not reading that much.

I did notice the rolling around laughing guy from Steve? I don't really know how to take that. It wasn't a joke.

Really, you'll do more from just putting these two parts together and wiring like you did back in the day. Pretend it's an old 'Vet, only prettier. You'll do good. Everything else that you are wondering about, with the VIN, can be done (and frankly, has to be done) with the ECU installed in the vehicle. It will have to have power, be turned on and be able to run the engine before any inspections can be performed, right? So, you'll have to get it running first.
Modified by Cyclemut at 8:28 PM 1/4/2010


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