Rb acting up after Gizzmo install? help

[rb25drag]

Alright guys I just got my Gizzmo tach and launch control installed on the Rb this weekend and wat a pain in the ***!!! Well I got it working correct. I bring it up to 3500 and it misfires and builds about 1-2 /lbs of boost.

At the time I just quick wired and taped until I knowed everything was going to be ok. I noticed last night every once in a blue moon while it was idling it would get a misfire and cut out. but I also noticed my lights in the car would blink at the same time.

So to day I went back over my wiring 3 times and everything is wired correct to my diagrams. So I took every wire back apart and re-wired soldered/shrink wrapped everything. Fire the car and now the misfire is getting worse. Could the launch control have burnt out my stock coil packs? Im only running on about 3 cyl now.

I brought the car up on the launch control about 8 - 9 times last night adjusting it. Is the stock coils not able to handle the misfiring or does it sound like something electrical? Last night it was running fine on all 6 cyl now today its down to about 3 and back firing and I didn't change any of the wiring.

[HxC_Nismo]

well after i installed my gizzmo launch interface on my rb the only ignition problem i had was my igniter chip fried on cyl #3 cause but it runs fine now after i replaced the igniter chip for me and i have my gizzmo set at 5400 rpm and i build about 3-5psi of boost. when i measured resistance on cyl 3 on the igniter chip i had really low resistance compared to all the other cylinders. it was around 1.xxxx and it was sopposed to be in the 8-9.xxxx ohms. check the resistance on all 6 cylinders on your igniter and let me know what you get.

[rb25drag]

Well I was able to mess with it for a short time last night. I hooked my volt meter up and did some testing. All the wires from the ECU are reading the same. So I went out to my coils. They were all the same except one #2 cyl.If I hooked it to the white wire they would all pegg the meter. If I hooked it to the black/yellow stripe wire they would read a lower voltage. Not sure of the numbers I was just random testing. But on number 2 cyl it was right opposite. White wire was putting out lower voltage and black/yellow wire was peggin my meter. I didnt get to test my igniter. Here's the curve ball tho, I noticed while I had it cranked my A/F gauge was running 22.1 % at idle!! which means its getting no fuel!!!! WTF?

Im going to run some more tests this weekend and try to find my prob. Ill do some ohms test on the igniter as well.

[HxC_Nismo]

keep me updated cause im currous on what it is, i would also take a noid light and check to see if your #2 cyl injector is working properly and also where is your fuel psi at? also did you make sure you had the gizzmo input and output wires done correctly with the ecu and engine side of the harness. also did you try to remove the gizzmo and see if it returns to normal? if so you might have a defective launch interface.

[rb25drag]

keep me updated cause im currous on what it is, i would also take a noid light and check to see if your #2 cyl injector is working properly and also where is your fuel psi at? also did you make sure you had the gizzmo input and output wires done correctly with the ecu and engine side of the harness. also did you try to remove the gizzmo and see if it returns to normal? if so you might have a defective launch interface.

Alright I got a chance to mess with it today. Fuel pressure regulator is set at 58PSI!! Re-checked the coils, igniter, Etc and its all getting the correct voltage!! So I decided to unhook the gizzmo launch interface re-wired the ecu back stock and problem solved. Everything is back to normal. So im assuming the interface is bad!! LOL my luck

[mello88]

Did you fix your fuel pressure? 43.5psi aka 3bar with the fpr vac hose unhooked.. sucks about the gizzmo is there some kind of warranty?

[rb25drag]

58psi is what I have had my fuel pressure setup as since I re-built the motor. Anything below 50-55 it runs too lean.

I am talking to gizzmo tech at the moment trying to fix the problem or get a new unit. When it worked correct it was nice!! and sounded awesome. Hopefully I can fix it.

[mello88]

doesn't sound right that's 15psi too much.. Are you compensating for smaller injectors by running more fuel pressure? What do you have for fuel tuning? W/E if it works for you...

[rb25drag]

I Still have the stock 370cc injectors. There maxed out, Prob beyond max. One day I will buy bigger injectors, Tuning I have a SAFCII, and a Wideband 02, for now until I can afford a PFC.

[JPsNissans]

You're on your way to blowing a motor up dude... Be smart.

[rb25drag]

You're on your way to blowing a motor up dude... Be smart.

Why do you say that? Its not like im running my motor lean! I have it tuned the best it can be for the setup I have. I have not skipped any corners with the internals of the engine I just cannot afford the externals I wont right now. This motor is bullet proof internally.

[Darius]

He is running a Z32 MAF and the motor is flowing more air than the MAF outputs when compared to the stock RB MAF. This is not very smart if you ask me, but at least you are watching your AFRs. Your fuel pressure has to be higher to correct for the reduced injector duration caused by your ECU still thinking the MAF is flowing less air than actual. It is probably most evident in the upper rpm range. I doubt you are maxing out your injectors too. How much boost are you running? I'm at 14 psi and I run them up to about 92% duty.

[rb25drag]

Im running 10lbs of boost. I cannot go any higher in boost!! it runs too lean and cuts out. Stock ECU and injectors are killing me!!

I also have higher than stock compression since my re-build.

Even using my SAFC I cannot get any more fuel out of my injectors so im pretty sure they are maxed!!

Every Rb owner I have talked too seems to be running higher boost, But im unable to.

Also When I first installed the motor it runs off stock waste gate at 4lbs of boost. I think most Stock Rb is 7lbs? So Im not sure if someone b/f me has changed something in the setup or not. But I do know I make as much power on 10lbs of boost than you guys are making at 14lbs of boost!!

But like I say its been a mystery box since I have owned it so im not sure whats up!!

[Darius]

rb25drag you are so thick headed sometimes! Seriously, change your MAF back to stock unless your SAFC has a table where you can enter in your own MAF values which I HIGHLY doubt it does. You car is running lean because the ECU doesn't see the amount of air that the engine is actually pumping through. Therefore, your "tune" is out of whack.

Higher compression doesn't mean crap with regard to AFR. What CR do you think you're running anyways? You aren't getting any more air in per cylinder. Your motor is just compressing it further. Giving you this ability to make the same power at 10 lbs of boost as guys running 14 lbs of boost, which I question. Maybe on the stock turbo it could be true. Anyways, compression only affects your knock limit which is dependant upon your fuel grade.

What are you running for a fuel pump anyways? Walbro I'm assuming?

And about boost, you need an aftermarket boost controller to raise it. I am not sure about the stock wastegate spring though??

And can you explain your wideband O2 plumbing setup for me? Is there a chance that you have a gasket leak upstream of the sensor that would allow oxygen into the exhaust pipe and trick your O2 sensor into showing that you were running lean?

[rb25drag]

I don't have a stock MAF I never received one with my swap. I was always told the z32 would work instead, Which so far it has.

Im running the 255 walbro fuel pump

I have a manual boost controller with a electronic solenoid to switch from stock waste gate to the manual controller.

I am running the Innovation Wide band. I have the Stock dump pipe I modified around the steering shaft Im running the wideband in place of the O2 sensor. No exhaust, just open Trust down pipe.

Compression im in the 9:8:1-10:1:1 ball park.My weisco pistons have a bigger compression dome than stock and we decked the motor to its manufacture limit on the block specs. 1.2mm head gasket with an 87mm bore.

Im stock ECU,Stock injectors, and Stock turbo to my knowledge, I was told the turbo was purchased new from Nissan b/f installed on my motor. All it says is Nissan and has no numbers on it. So as far as I know its stock t25.

This is also a S1 motor.

This motor also runs better on racing fuel 112 octain. Has alot better throttle response!!!

[Darius]

Alright with respect to your fueling issue here is an analogy:

Running a different MAF than what your ECU was setup for is like wearing shoes that are 5 sizes too big. They appear to do the job when you are walking. But when you are sprinting, the mismatch impedes performance. Find yourself an equivalent MAF (there is another MAF thread floating around on the first page of the forum right now. Or search "maxima") and slap that on there. You should not be maxing out your fueling system unless you are having to run rich to keep from knocking.

For the boost issue, you can try running solely on the stock WG spring by running a boost line from your cold pipe to the actuator diaphragm. In the FSM, it says to test the gate operation with compressed air at 385mmHg which is 7.44 psi. So I assume the stock gate has a 7 psi spring in it. To run higher boost than the stock spring, you need to create a 3psi loss in boost pressure between the cold pipe and actuator so the 7 psi gate opens when you run 10 psi. If you want to run 14 psi, you need to create a 7 psi leak. Get it? That is what your manual boost controller should be doing for you already. Why it does not create a larger leak than 3 psi is beyond me.

How are you monitoring knock? I ask because I don't think I would be running higher compression and trying to increase boost without watching that constantly. Especially on the top end.

[rb25drag]

So a Maxima MAf will work? If so what years?

I am monitoring knock with my SAFC, I have not seen any knock since the rebuild.

If and when I get the Power commander can I use the z32 Maf?

Also what Hp ratings are our injectors good for?

I have not dynoed the car yet due to lack of tuning tools but I calculated my track times and it shows to be around 340WHP?

I run 7.80's in the 1/8 mile untuned and no launch control, also bad transmission slave so no power shifting.

Thanks for the info!!

[gawdzilla]

i'm probably not the only one who thinks this entire "build" is a little fishy, but anyway... i guess that is besides the point.

maxima green label maf is the s1 stock maf. probably like 93-97 years.

running the wideband sensor in location of the stock o2 sensor will kill the sensor. egts are too hot there and if it isn't already giving you false readings it will soon.

don't power shift on the rb25 trans. it will break the trans unless your clutch is the weaker of the two.

stock 370cc's can probably do right around 300-320 whp reasonably. probably will be way above 80% duty cycle but it'll work ok.

[rb25drag]

Sorry you guys think its fishy!! But I have got and told you guys everything I have done and built and how its performed.

Were are you guys running the Wideband o2 then?

My clutch isnt the weak link. Stage 4 Cusco Exedy twin plate. So far my weakest links have been the driveshaft and the rear axles.

So what are you guys running E:T wise at the track stock Rb? 1/8 mile? 60's?

Also can I use the z32 MAF with the Power Fc commander?

[Darius]

I have a second O2 bung welded into the end of my downpipe about 4-5ft from the turbo. It was good of gawdzilla to mention that.

I'm a little embarassed to tell you that I have only run a 14.2 at 100mph, but that is because I had 205/55 all-season tires and major wheel hop becuase of it. Plus, I'm running lower compression than stock with stock turbo and intercooler. Things will be different next spring, but for now that is where I'm at.

Once you get a PFC, there is a setting on the hand controller to allow you to select from the stock MAF, Z32, Q45, and a custom MAF where you can enter in values for something custom.

[rb25drag]

Ok thanks for the info about the o2. Now is it going to change my reading if I don't run any exhaust? B/C I am running open down pipe and I have no plans to change it. Also would it be smart to put the wideband in the center of the down pipe due to no exhaust or does it matter the location?

The PFC is on my list for next purchase.

LOL I couldnt imagine 205 all season tires on the track!! You prob spun threw 4th gear!!!

Mine has 26 x 11.50 M:T street slick and has went 1.6 60' with a 5800RPM launch and the best of 7.81 @ 91 MPH in the 1/8th. I don't have a 1/4 mile track within 4 hrs of me. I wish I did tho!!

I do not daily drive this car. Its street legal but with my tight clutch and posi rear end and open down pipe im like a stripper in a bar!!! Everyone notices so I mostly drag the car at the track. I do drive it on occasion but usually only 1st a month if that.

Thanks for the info again!!

[rb25drag]

Ok thanks for the info about the o2. Now is it going to change my reading if I don't run any exhaust? B/C I am running open down pipe and I have no plans to change it. Also would it be smart to put the wideband in the center of the down pipe due to no exhaust or does it matter the location?

The PFC is on my list for next purchase.

LOL I couldnt imagine 205 all season tires on the track!! You prob spun threw 4th gear!!!

Mine has 26 x 11.50 M:T street slick and has went 1.6 60' with a 5800RPM launch and the best of 7.81 @ 91 MPH in the 1/8th. I don't have a 1/4 mile track within 4 hrs of me. I wish I did tho!!

I do not daily drive this car. Its street legal but with my tight clutch and posi rear end and open down pipe im like a stripper in a bar!!! Everyone notices so I mostly drag the car at the track. I do drive it on occasion but usually only 1st a month if that.

Thanks for the info again!!

[Darius]

Running an open down pipe won't change your readings unless you have a leak at one of the gaskets upstream of the sensor like I explained earlier. There are actually wideband O2 sensor kits that come with a tailpipe attachment to place the sensor about 12" into the tailpipe.

Yeah I can't launch the car at all or I get crazy wheel hop. I think I launched it twice. Once at 2500 rpms and that's when I broke my driveshaft. And the second time I did it after I replaced my driveshaft and subframe bushings and it hooked up pretty good initially but started to spin in the middle of first. I can't wait until spring.

Keep us posted on what you find with Gizzmo BTW. I'm interested in getting one later on if the budget allows.

[rb25drag]

I can weld my own bung in the down pipe. Not a problem there.

I have never experienced wheel hop! Of course I have always ran a welded diff too.

On my 6,000 launch my dad said it brought my front wheels about an inch off the ground before I snapped both axles Those M:T Tires never spun a round!!!

The gizzmo tech has sent me a new launch interface so as soon as I get it im going to see what happens. Im really hoping it was just a bad interface. If it happens again then something is screwed!!!!

I wanna be the first Nissan guy to pull a wheelstand out of a 240 with a Rb. I have never seen it done b/f. Can it be done?

[Darius]

Hey did you get the Gizzmo thing sorted out? I have heard on some of the Aussie sites that they were having problems with defective control units. Did you get a new one sent to you and did you install it yet?

[rb25drag]

Ya I got it working. I contacted the company and they were very helpful and sent me a replacement no questions asked. I was satisfied with there tech help! The new unit seems to work good. I have only used it twice tho! I pulled the motor after the second launch!

[Joe]

I Still have the stock 370cc injectors. There maxed out, Prob beyond max. One day I will buy bigger injectors, Tuning I have a SAFCII, and a Wideband 02, for now until I can afford a PFC.

oh my goddude NO

STOP NOW

that is a guaranteed way to blow your engine apart.

never EVER run your injectors at 100% duty, you have no idea what a timebomb it is.

[rb25drag]

Don't worry!!! Its ok, Im getting rid of them A.S.A.P, Im going Propane remember!! My other threads!

[rb25drag]

Im still playing with the Gizzmo, Its a funny unit to figure out. But I took some video of a 3600RPM, and 4000rpm launch, im doing these test in neutral. Boost gauge is on the left.

The first video is from 3600RPM's, I seem to build about 5-6PSI according to how long I hold it on the launch control.



The second video is on a 4,000RPM launch and I don't hold it long at all. Just with a 400RPM difference I get a 11PSI out of the 4,000 launch. Nearly 6PSI difference out of the 400RPM's.



I have not been able to get a track pass yet. I have a new wheel combination im going to try within the next few weeks. So I hope for some good results.

[slowrb20]

my fastest 8th mile time was 8.55 at 15psi with the setup in my sig and no traction what so ever