supercoupe issues..

[LSx S10]

you guys might have seen my thread about the 90 thunderbird supercoupe ive been working on for a friend. i finally got it running and driving perfect, drove it all over with no issues. he finally comes to pick it up. calls me about 20 mins later and tells me while he was driving all the dash lights turned on and like a flick of a switch the engine shut off. no sputtering just went from running perfect to dead.
got it towed back to my house. so far ive found that there is no spark, no injector pulsing, and while it cranks the rpm's stay at 0. figured it was the crank position sensor, which is located conveniantly behind the harmonic balancer. i checked all the fuses and the only blown fuse is a 5A for the ecm memory. so now im thinking its a fried ecm. the crank position sensor controls spark and the camshaft position sensor controls injector pulsing. and there is no way both those sensors fried at the exact same time. So am i right in thinking the ecm is fried? and if it is why would that happens, something to do with the fact that the car has been sitting for a pretty long time?

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[Dasfinc]

Stupid question... Have you tried replacing the fuse?

It pops to PROTECT the ECU from frying...

The next question would then be "why did it pop" and I'd start looking for rotted/bad/loose grounds since its been sitting so long and its an old car.

 

[LSx S10]

yup replaced it and nothing

 

[Dasfinc]

yup replaced it and nothing

I know its a 1990, but is it OBD1? IIRC you can jump the EEC connectors in the motor bay somewhere and it will show you CEL codes. (or it will show you nothing, in which case the ECU is most likely dead)

Does the CE light turn on when you turn the key to the 'on' position, etc.

 

[WhiteDevil]

Id check the grounds and check ANY lead ins from those sensors to the ECM to see, I know you got a wire probe.

 

[LSx S10]

yea ive got a check engine light

i actually just bought a power probe off the matco truck at work on saturday, greatest tool ever, get to use that bad boy

 

[Dasfinc]

yea ive got a check engine light

i actually just bought a power probe off the matco truck at work on saturday, greatest tool ever, get to use that bad boy

in that case

Id check the grounds and check ANY lead ins from those sensors to the ECM to see, I know you got a wire probe.

X2

Again, if you can, do the EEC-V Jump and read what codes the ECU has in it.

 

[LSx S10]

i borrowed a genysys from work and was not able to pull any codes off of it, even though the light was on. i was able to do the self diagnostic KOEO and KOER tests but still found no codes, but i was able to connect (this was when i was diagnosing the high idle)

 

[RebelGTP]

tell him to give it up and buy something else... ROFL

 

[LSx S10]

i agree, im pretty sick of working on it. but it is pretty fun. it drives like a more civilized version of a stock fox body. the same pull but its quiet and smooth. all you hear is whine

 

[bikrboy128]

i borrowed a genysys from work and was not able to pull any codes off of it, even though the light was on. i was able to do the self diagnostic KOEO and KOER tests but still found no codes, but i was able to connect (this was when i was diagnosing the high idle)

well of course you arent going to get codes, the ecm memory was cleared when the fuse popped.

like whitedevil said, check your grounds and wires from the ecm. the ecm may very well have fried.

 

[Dasfinc]

i borrowed a genysys from work and was not able to pull any codes off of it, even though the light was on. i was able to do the self diagnostic KOEO and KOER tests but still found no codes, but i was able to connect (this was when i was diagnosing the high idle)

well of course you arent going to get codes, the ecm memory was cleared when the fuse popped.

like whitedevil said, check your grounds and wires from the ecm. the ecm may very well have fried.

Maybe I'm reading it wrong, but I'm reading "not able to pull any codes" as "I am unable to get anything from the ECM." not "the Genysys comes up with "No codes found" "

These are 2 different things, can you clarify tony?

 

[Mickey]

yea ive got a check engine light

i actually just bought a power probe off the matco truck at work on saturday, greatest tool ever, get to use that bad boy

What do you think you're going to do with the powerprobe in this situation?

 

[LSx S10]

i dont have the scan tool now, this was earlier when i was first working on it. i actually forgot i was able to pull one code. it was for "not in neutral/park during start up" something along those lines.

What do you think you're going to do with the powerprobe in this situation?

we are talking about the same thing right? what im thinking of would be very useful in this situation because you can use it to test ground integrity, continuity, supply a good ground, etc...

 

[Dasfinc]

i dont have the scan tool now, this was earlier when i was first working on it. i actually forgot i was able to pull one code. it was for "not in neutral/park during start up" something along those lines.

IIRC some cars can be VERY stupid when it comes to code-reading, and will often 'Bail out' of a code-reading test if you don't set everything up correctly.

(What I mean is Because you got that "not in neutral" thing, it may have stopped right there and never actually pulled any other codes)

Regardless, to clarify again, You received that "Not in neutral" error AFTER the car died and was towed to your house? or back when you were first working on it?

 

[Mickey]

Does the power probe show voltages?

 

[LSx S10]

IIRC some cars can be VERY stupid when it comes to code-reading, and will often 'Bail out' of a code-reading test if you don't set everything up correctly.

(What I mean is Because you got that "not in neutral" thing, it may have stopped right there and never actually pulled any other codes)

Regardless, to clarify again, You received that "Not in neutral" error AFTER the car died and was towed to your house? or back when you were first working on it?

this was back before the car died. but the thing is..the car is a 5spd manual, and it was in neutral considering i was doing a KOER test, and was in neutral when i started it.

Does the power probe show voltages?

yes it does, has a digital display. you can also supply a voltage with it but a lot of people have fried ecms by accident with them so youve gotta pay attention. it was worth every penny though.

 

[WhiteDevil]

DO you have ANY power in the vehicle?

 

[Poopshinanigans]

If the computer is the problem you can find them on ebay pretty easily.

 

[Dasfinc]

this was back before the car died. but the thing is..the car is a 5spd manual, and it was in neutral considering i was doing a KOER test, and was in neutral when i started it.

Ok, You need to listen, No offense.

I said earlier that essentially: "Try to check the codes NOW", not having any codes before the car died isn't gonna help right now.

If the car died, and its electronic related, chances are its gonna either be toast (as in cannot pull codes), or it will say no codes STORED, in which case the ECU may still be good.

Even with the memory fuse popped, OBD1 ECU's CAN store codes unless erased BY a code-reader (even with no power)

 

[WhiteDevil]

Might be the Solenoid for the starter, it is the main power point for the vehicle.

 

[Bob Kazamakis]

i just watch the LED.... honda...

 

[Mickey]

When you replaced the 5A fuse did it pop immediately? Does this car have an aftermarket stereo system? The 5A fuse powers the gauge cluster, the stereo, the HVAC function switch, LCD illumination, rear defrost and the maintenance minder.

 

[LSx S10]

When you replaced the 5A fuse did it pop immediately? Does this car have an aftermarket stereo system? The 5A fuse powers the gauge cluster, the stereo, the HVAC function switch, LCD illumination, rear defrost and the maintenance minder.

no, hasnt popped and its been in there since i replaced it on the side of the road. yes it has an aftermarket stereo but it doesnt work. everything else you listed does though.


Ok jumped the pins, no codes flashed. i dont have the scan tool anymore so i cant check it that way. Ive been on the sc owners club and they told me if the upshift light doesnt turn off while cranking than its the crankposition sensor. well that light does not turn off. i unplugged the CPS and tried starting it but no start. the fuel pump does not turn on while cranking either. and like i said before no spark and no injector pulse. all my symptoms are screaming crank position sensor, and i already bought it so im just gonna tear it down and replace it. if it doesnt fix it then ill keep right on troubleshooting.

 

[LSx S10]

i need to stop second guessing myself. it was the crank sensor. finally broke down today and pulled off the harmonic balancer and replaced it. started right up when i got it all back together. whole thing took less than a half hour so it wasnt as bad as i thought it would be.