Well I'm back after a long hiatus and getting ready to dig back into this car. The silver MSP will be gone by the end of May, so I'll have cash for the Pulsar. Hindsight's 20/20 I should have left the OEM ECU in place and just tried out the engine that way, but what's done is done. I know Dee will say go SDS or nothing, but since this is most likely a wiring problem, I'm curious if I could buy a harness from Wiring Specialties (http://www.wiringspecialties.com/wsprs13srins4.html) to see if that will resolve my problem. I'll have to extend some of the connectors, but that's not difficult. Also, someone remind me what the brown and white plugs are that dangle just off the left side of the ECU plug?

They go up into the dash and have signals for starting, speed (not needed), tach output, water temp gauge signal.... and I think that's it. It's been a LONG time since I had to mess with one.

After doing a lot of research and speaking with some sales reps at DIYAutoTune, I've decided to go with Megasquirt 3 with the MS3X expansion board. They have programming for the factory Nissan CAS in the MS3 source code now, and it's apparently reliable now. If that doesn't pan out, I can install a trigger wheel and hall sensor and that's all I need to control the ignition. The MS3X expansion board also has sequential injection/ignition control, which is a nice improvement over the batch/bank options of other EMS kits.

I plan on doing a wire tuck as well, because if I'm re-wiring the car, might as well clean up the engine bay while I'm at it. Also while cleaning I'm going to install a vacuum pump to control the power valve and get rid of the canister and vacuum mess.

One question I have is about the fuel filter. Is it really necessary anymore? These cars were from the 80s when fuel standards were pretty crappy. It would be nice to get rid of that thing because it clutters up the engine bay.

I would always always always use a fuel filter. It doesn't take too much to clog an injector and really make a big mess inside the motor due to inadequate fuel flow. A small particle of dirt in the injector because you didn't have a fuel filter in place can clog or partially clog an injector very easily and possibly lead to a lean cyl and BOOM! You can never be too careful. Just my thoughts...

Also, a simple solution to the clutter issue would be to relocate the filter. It doesn't HAVE to be in the engine bay. In my racecars, I have mine right next to the fuel cell under the car. Not sure what your routing looks like or how crazy you went with the fuel system, but that may help you.

Good point. I'll see if I can move it lower in the engine bay or back by the fuel tank under the car.

livelyjay wrote:Good point. I'll see if I can move it lower in the engine bay or back by the fuel tank under the car.

There you go brother!

And so it begins. It was like Christmas today as I got five boxes delivered to the house. Made some good progress and I only really worked on the stuff for about an hour total.

Soldering station set up with all the parts laid out:


Relay board parts laid out:


Relay board assembled:


Bottom side of relay board:


Test board parts laid out:


All resistors soldered to the board:

Wow, you are a brave soul . Even though I use the SDS systems, I encourage anyone to use whatever engine management system you want or your pocket can afford. So I would never tell you "Go SDS or nothing" because again, your money is not my money and my experiences is not your experiences. But I can make a recommendation because it is something that is available, tried and proven to work well on our engine's platform. I hope you can get the MegaSquirt to function the way you like, so that you can encourage other members to seek other avenues of engine management if their current set-ups are not functioning the way they would like. Lastly, congratulations on your purchase and I truly hope this is the one key that will get your engine going smoothly. Mad respect for you, brother

Thanks for the support Dee, and this is in no way undermining SDS and the services you provide to the CA community. I spent a lot of time talking with the MS reps about this one. I wanted the experience of building up the ECU from scratch, for some reason, maybe I'm just crazy. The MS rep just answered all of my questions with as much information as he had and I found other bits and pieces on the forums and in their online manuals. The platform has come a long way since MS2. In theory someone nailed down the decoding of the OEM CAS so I won't have to change out my ignition. If that decoding doesn't work, then all I need to do is install a trigger wheel and hall sensor. Since this entire Pulsar project is supposed to be a learning experience, doing the MS3 from scratch is the best way to force me to learn all I can about micro-controllers, fuel injection, and ignition timing.

I'll keep my fingers crossed that this learning process doesn't hurt my engine in any way, which is why I plan on taking things slow.

I also have a very vested interest in pulling this off. I made a deal with myself that if I can't get this thing running then I'm not allowed to buy a mid-life crisis car, be it a kit car or something fancy like an Acura NSX

LOL! I hope it works out for you. If the stock CAS can be made to work, that would be a huge gain for the CA18 community.

Lots of progress between Friday and Saturday.

Test board done


Main board components


Resistors done


Diodes done


Capacitors done


Final components fitted


Testing board power - successful


Ignition trigger jumpers added + MAP sensor

Added Tach input pullup jumper and resistor. This is necessary to use stock Nissan CAS:



Jumper to the MS3X board for using the 6 solenoid outputs:


Fully assembled:



All components:


Firmware uploading:

And then what happened?!?!?

Then it finished successfully. I purchased a license for TunerStudio and hooked that up. The inputs from the test board showed up in the TunerStudio dashboard, so it's my best guess that things are working correctly. Now it's on to the hard part, configuring everything for CA18DET. I'm going to play around with TunerStudio and the test board a bit just so I can be comfortable with what it's all doing. I didn't see the Nissan CAS in the test board configuration, but I might have just missed it. I also plan on doing a lot of reading these next few weeks about the MS and configuration, as well as finding a tuner.

Nice!

I just found some documentation for the factory coolant sensor so I think I'm going to try and use that instead of the GM sensor that MS is calibrated for by default, mostly because I don't want to have to drill and tap the stock location and I don't want to find an alternative location for the GM sensor. I don't have a welder anymore, so I'll have to find some alternative to welding on the bung for the intake air temp sensor. I don't think the factory IM has a spot for it so I should be putting it in my cold pipe right next to the TB correct?

Yea, that's where I put mine. SDS always said NOT to put it in the IM because it can heat soak and the extra vibrations make the sensor fail early. As for a bung, look into brazing. It can usually be done with MAP gas.

I didn't know you could braise stainless steel. I have some MAP gas I think, otherwise I can just pick up another tank of it.

Some additional bench testing of the rig. The JimStim is kind of useless if you're running the MS3X board because the spark, injectors, idle, etc are coming out of the other DB37 connection. There is an additional stim you can buy for $44, but I didn't know I'd need it. Instead I used one of the supplied solder-cup DB37 connectors, soldered in some jumper wires, and jammed them into a bread board. I got the spark to blink some LEDs, but the injectors and idle output, according to the documentation, run the other way around (ground at ECU, voltage coming into injectors/idle valve). So tonight I'll run 5V to the injector LEDs and idle valve and see if I can get those signals to show up. Once I make sure the ECU is working, I'll bring in the stuff off of the car and start bench testing with the real equipment. I'll also figure out which output I'll be using for the power valve solenoid, which I'll probably hook up using that vacuum pump thing suggested here on the forum.

Jumping ahead of myself, but what should I use for a base map? I figured using the base SR20DET maps that are floating around might be a good start because I couldn't find any CA18DET base maps.

I would think an SR20 base map should be close enough to work with and get it running. Be aware that the CA needs less timing than the SR though, so you might pull a few degrees of timing off the whole map right off the bat. Fueling requirements should be similar.

Thanks float, I'll look into that when I load up the mapping.

Got the secondary test board soldered up and it's working. The entire ECU appears to be working well and I can run full sequential mode. Tomorrow I'll pull the CAS off of the car and wire it up as the RPM input. I'll need to do a lot of wiring as the primary test board will be taken off of the DB37 connector so I can hook up the CAS. I'll either have to jumper the test board or hook up the full relay board and wire everything up. It'll look messy, but it should provide me with the closest bench test without having to install everything on the actual car.

Picking a color to paint your car I think it tougher than picking one for a room in your house. Mostly because the paint is 5x as expensive and 100x more difficult to apply. Leaning towards BMW Imola Red, but there are a lot of good red colors out there: Audi Brilliant Red, VW Volcano Red, Mazda Velocity Red Mica, Honda Milano Red & New Formula Red. Tough to choose.