Car starts then dies. $15 paypal right now to anyone who can diagnose my problem.
07-28-2007, 02:22 PM
#1
Car starts then dies. $15 paypal right now to anyone who can diagnose my problem. Allright $15 bucks gets sent to your paypal if you diagnose my problem! I've been building a 95 TA for a while and were trying to get it done to go to Ocean City this tuesday.
It starts up then dies. If I hold an injector in my hand it feels like it stops pulsing a few seconds before it dies. Spark seems to stay strong untill the motor is completely dead.
It's a 95 A4 Trans am with a 95 obdI PCM with a pcmforless tune with vats removed, a 96 OBDII M6 engine harness. I disabled the VATS starter kill relay. Tried 2 previously working optis. 2 PCM power wires did not match pin to pin where the engine harness connects by the pas kick pannel. We only found one PCM pwer wire on the car harness and 2 on the engine harness so we spliced the 3 together. It starts and runs long enough to blip the throttle mayby 2 times and it sounds healthy, then it falls on it face completely like there were no more injector pulses or no more spark.
It's a new 255lph pump. I verified power at the pump. It has power from the time you crank to a few seconds past when it dies. The car is ready to go other than this!
Oddly if I swap in my stock tune PCM it runs like 4 seconds longer than the OBDI tuned computer.
Post here and or call me if you have ANY ideas.
-Tyler
-724 456 7710
It starts up then dies. If I hold an injector in my hand it feels like it stops pulsing a few seconds before it dies. Spark seems to stay strong untill the motor is completely dead.
It's a 95 A4 Trans am with a 95 obdI PCM with a pcmforless tune with vats removed, a 96 OBDII M6 engine harness. I disabled the VATS starter kill relay. Tried 2 previously working optis. 2 PCM power wires did not match pin to pin where the engine harness connects by the pas kick pannel. We only found one PCM pwer wire on the car harness and 2 on the engine harness so we spliced the 3 together. It starts and runs long enough to blip the throttle mayby 2 times and it sounds healthy, then it falls on it face completely like there were no more injector pulses or no more spark.
It's a new 255lph pump. I verified power at the pump. It has power from the time you crank to a few seconds past when it dies. The car is ready to go other than this!
Oddly if I swap in my stock tune PCM it runs like 4 seconds longer than the OBDI tuned computer.
Post here and or call me if you have ANY ideas.
-Tyler
-724 456 7710
07-28-2007, 02:34 PM
#2
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Originally Posted by tylert14
Allright $15 bucks gets sent to your paypal if you diagnose my problem! I've been building a 95 TA for a while and were trying to get it done to go to Ocean City this tuesday.
It starts up then dies. If I hold an injector in my hand it feels like it stops pulsing a few seconds before it dies. Spark seems to stay strong untill the motor is completely dead.
It's a 95 A4 Trans am with a 95 obdI PCM with a pcmforless tune with vats removed, a 96 OBDII M6 engine harness. I disabled the VATS starter kill relay. Tried 2 previously working optis. 2 PCM power wires did not match pin to pin where the engine harness connects by the pas kick pannel. We only found one PCM pwer wire on the car harness and 2 on the engine harness so we spliced the 3 together. It starts and runs long enough to blip the throttle mayby 2 times and it sounds healthy, then it falls on it face completely like there were no more injector pulses or no more spark.
It's a new 255lph pump. I verified power at the pump. It has power from the time you crank to a few seconds past when it dies. The car is ready to go other than this!
Oddly if I swap in my stock tune PCM it runs like 4 seconds longer than the OBDI tuned computer.
Post here and or call me if you have ANY ideas.
-Tyler
-724 456 7710
It starts up then dies. If I hold an injector in my hand it feels like it stops pulsing a few seconds before it dies. Spark seems to stay strong untill the motor is completely dead.
It's a 95 A4 Trans am with a 95 obdI PCM with a pcmforless tune with vats removed, a 96 OBDII M6 engine harness. I disabled the VATS starter kill relay. Tried 2 previously working optis. 2 PCM power wires did not match pin to pin where the engine harness connects by the pas kick pannel. We only found one PCM pwer wire on the car harness and 2 on the engine harness so we spliced the 3 together. It starts and runs long enough to blip the throttle mayby 2 times and it sounds healthy, then it falls on it face completely like there were no more injector pulses or no more spark.
It's a new 255lph pump. I verified power at the pump. It has power from the time you crank to a few seconds past when it dies. The car is ready to go other than this!
Oddly if I swap in my stock tune PCM it runs like 4 seconds longer than the OBDI tuned computer.
Post here and or call me if you have ANY ideas.
-Tyler
-724 456 7710
07-28-2007, 03:29 PM
#3
The pink engine harness wire goes to the pink chassis harness wire which is a fused start run and test circuit. The orange engine harness wire is supposed to go to a allways got pcm bat fuse but my 95 chassis harness dosen't have provisions for it because the 95 engine harness has it's "pcm bat fuse " in the underhood fuse box not the interior one.
So I rand a fused always hot wire to the orange engine harness wire.
So my PCM power is working just as it did stock to the best of my knowledge so I guess it's not that.
Next?
So I rand a fused always hot wire to the orange engine harness wire.
So my PCM power is working just as it did stock to the best of my knowledge so I guess it's not that.
Next?
07-28-2007, 05:05 PM
#7
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hey man, this is simple. Check fuel, check spark, if you have both then you know its ecu related, get a noid light and check the injectors, whats the fuel pressure, did the car run before this or is this a fresh buildup?
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07-28-2007, 05:40 PM
#8
Did you check your ECT (Engine Coolant Temp) sensor? (Located in the water pump.) It's a key component in telling the PCM how much fuel to pump through the injectors. If it goes bad, it will cause an extreme rich condition. Your engine may just be getting too flooded to start.
07-28-2007, 06:18 PM
#10
It has spark and fuel at startup. The fuel pump stays on but it seems like something is cutting out the injector pulse. We checked the wiring harness and got that all figured out. Vats shouldnt be a problem I swapped the steering column but I switched the resistor originaly from this car into the key for the new column.
Anyone else have any ideas?
Anyone else have any ideas?
07-28-2007, 06:33 PM
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well its probly not this.. but heres what iv experienced. my buddy built a 97 supra single turbo, he had the aem tuning software.. it did the same thing. he thought his aem was bad.. he thought his pcm was bad yada yada yada. well it turned out to be he wasnt getting enough fuel to the motor. it showed alot on the tuner.. but it wasnt getting any of what it said.. so he added and added and finally it ran. air in the lines possible.. or pcmforless didnt do your fuel table.
07-28-2007, 06:52 PM
#14
Take your IAC out, verify proper length as if it is a new install. Reinstall it, keep your IAC disconnected and try it.
I think your IAC broke in an position where it wont idle, and keep AC off.
Just my 2 cents.
I think your IAC broke in an position where it wont idle, and keep AC off.
Just my 2 cents.
07-28-2007, 06:56 PM
#15
I tried a diferent ECT and ICM with the same results. With a spare injector in my hand hooked up to a FI connector I can feel roughly 7 pulses then it stops and the engine runs for about 3 more seconds.
We tryed my PCM in my buddies Trans Am and it worked fine.
For some reason the PCM is stopping the injectors from firing in my car.
Bryan did mention something about "Corvette Vats" that is a seperate thing you can disable for VATS. He said it was only for lt1'd vettes but he had some people with harness swaps having problems. He dosen't normaly disable "corvette vats" and he didn't on mine... I don't see why that would matter though because I have the correct value key pellet.
Also, I have an 96 M6 TA steering column in the car. The M6 ignition switch wouldn't be causing this would it?
We tryed my PCM in my buddies Trans Am and it worked fine.
For some reason the PCM is stopping the injectors from firing in my car.
Bryan did mention something about "Corvette Vats" that is a seperate thing you can disable for VATS. He said it was only for lt1'd vettes but he had some people with harness swaps having problems. He dosen't normaly disable "corvette vats" and he didn't on mine... I don't see why that would matter though because I have the correct value key pellet.
Also, I have an 96 M6 TA steering column in the car. The M6 ignition switch wouldn't be causing this would it?
07-28-2007, 07:49 PM
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Originally Posted by tylert14
Hmmmm stupid question. And this one dosen't get you $ if you answer lmao...
I broke my low oil sensor when I built the motor so I left it disconnected. Would that make it shut the motor off? Doubt it but worth a shot...
I broke my low oil sensor when I built the motor so I left it disconnected. Would that make it shut the motor off? Doubt it but worth a shot...
07-28-2007, 08:30 PM
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idk about 95's but my 94 t/a ran with no oil pressure till the lifters started chattering.lost my oil pump drive gear on my fairly new 355.the low oil light was not on as there was still oil in the pan.i do believe i have got the low oil light to turn on in some hard cornering and it stayed running without a hicup.