Quote: Fuel pump does not prime like a chebbie when the key goes on. Fuel pump runs in ign start without ecu control. In ign run, FP runs under ecu control - ecu keeps pump turned on as long as it sees an rpm signal from the coils. There is an FP test terminal somewhere - check fsm - that will run the pump when you apply 12v+ to the terminal with a jumper wire.
Dead ecu's are most often bad capacitors leaking and eating circuit board traces, accompanied by a fishy smell in the ecu. If the CEL is now off in the check bulb mode, (do the other lights check on key on?), most likely it's ecu rebuild time, or a dead bulb.
I never worked on a chevy, I mainly dedicated my time to Nissans and Toyotas, but good to know.
But to your question: they do indeed all turn on as usual, and the CEL comes back on after being left alone for a few hours and starting it back up (the codes are intermittently being stored in the ECU I suppose?).
I think what finally affirmed my suspicion that its a bad ecu is that I got it to start up for a 5th time with a functional CEL displayed in self check and I let it idle, while I inspected the fuel pump for irregularities (signs of strain/high pitch sounds). None were observed.
I then decided to cycle through the gears (its auto) and when I put into D the car immediately died. I'm guessing the ECU couldn't compensate for the change in a/f ratios its suppose to go into when going from Park to Drive--just an educated guess since I never worked on autos, either. It was followed by a loud sound near the glove box area, I had the hinges removed trying to locate the code reader/fuel pump 'jump' connection.
I'm going to pull the ECU and look at the internals to see/smell for myself. The walkthrough on avp's site to ID faulty capacitors is quite useful.
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