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Bad keydiver ECU? (pics)

Barnes

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Feb 9, 2003
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So the reason my white car stopped working is my ECU died. The thing I don't get is that this is an ECU that was sent to keydiver, repaired, chipped, and sent back. It worked fine for a couple years and suddenly died. I can't see any visual damage. I can smell a faint odor of fried PCB, but only if I put my nose right up to the board, and it might just be residue from past capacitors failing. The car would crank but not start. It seemed to have fuel, but no spark. I have no idea what could have failed on the board. Any thoughts?
 
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ktmrider

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Tempe, AZ
Pics may help.

The one or more drivers and/or power supplies could easily have gone bad, I wouldn't necessarily put it out as a fault of Jeff's mineself...
 

Barnes

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I'm not blaming Jeff, it's just unusual for an ecu that's been repaired by him to go bad. It was one of the last things I suspected.

I could take a picture, but I don't think there is anything to show. It looks perfectly fine. I'll try to do that soon.
 

desant78

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This is scray, possible other than caps another component is failing after 20+ years of use? I might just be paranoid, but I'm following this thread.
 

cheekychimp

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Barnes, I know you are not one to jump to conclusions, but if the ECU appears fine have you confirmed that the ECU is at fault by either putting this ECU into another car or using a known good ECU in your car?
 
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Barnes

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I put a known good ecu and the car starts fine.
 

grocery_getter

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When you said you have fuel, did you verify the injector operation by using a noid light? Otherwise, have you verify that the injector is opening/closing?

Since another known good ecu did start the car, the failure to start *in your particular car* could be caused by 2 things. If your injector didn't cycle open/close, then it is most likely a bad CAS input circuit, if your injector did cycle open/close the its likely a bad spark output circuit.
 

Barnes

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Richland, WA
I'll try to double check. The plugs sure looked wet with fuel (and smelled), but when I took the CAS out and spun it by hand I didn't hear the injectors. However I don't know if you can just hear them. But I know fore sure the spark plugs didn't fire.
 

desant78

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I can verify that you will hear clicking by the injectors by just spinning the CAS to check if they are working (assuming you took the proper steps for this test). The noise isn't super loud, but easily noticable. If you pull the plugs and let them rest on your valve cover, you should see them individually spark too.

Good luck! - and please leave the car in nuetral, or you might get a suprise....ask me how I know that /ubbthreads/images/graemlins/uhh.gif
 

grocery_getter

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You can buy a single 12v LED from radioshack for under $2 and have a positive blink or no blink with the injectors. Good to keep in the tool box for future troubleshooting with ANY efi car.

Quoting Barnes:
I'll try to double check. The plugs sure looked wet with fuel (and smelled), but when I took the CAS out and spun it by hand I didn't hear the injectors. However I don't know if you can just hear them. But I know fore sure the spark plugs didn't fire.

 
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Barnes

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Richland, WA
To check spark I pulled the COP setup and laid it on the intake manifold with the plugs grounded to the manifold.

Thanks for the tip Andre. I'll try to snag one of those.
 
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