92 Bonneville Stalling/Not Starting Problem
So I've had a problem similar to many on this forum. It started with difficult starts. It would sometimes take 5 or 6 tries to turn over. Over about a week of driving, the car began stalling intermittently. Eventually it would stall consistently when running temperature was reached, after 5-15 minutes. It seemed that low fuel pressure could be a probable cause. So I replaced the fuel filter. As a side note, when working underneath the car with my buddy we bumped the power steering coolant line and cracked the it next to the radiator. So that was replaced as well. The problem appeared to go away after replacing these two items.
Unfortunately after about 15 minutes into a test drive the car died again. I could wait about 5 minutes and then restart. I eventually got her back to the house. Through some searching I learned how to pull the codes from the computer. I got the normal code 12 followed by a code 21 (Throttle Position Sensor - High Voltage). So I replaced the throttle position sensor and set the range with a voltmeter. The code 21 eventually went away, but I still have a check engine and service engine soon light on.
I then replaced the camshaft sensor with no noticeable change. Then the crankshaft position sensor. After this the problem worsened with the car only running for 3-5 seconds. I can usually extend the run time by a few seconds if I throttle it up. After all the cranking, my battery is now low so I have to get a jump when starting. But the alternator is pushing out 14.5 volts. I've checked all the fuses, accessible grounds, cleaned throttle assembly and sensors (including MAF), regapped and cleaned up spark plugs. Checked fuel pressure, it'* at 42 psi primed and 38 psi running. I was able to replicate the stall while the engine idled after the car reached operating temperatures and the fuel pressure went back up to 42.
Now when I check the codes by jumping the A-B terminals, the car dings four or five times in rapid succession (sounds like a bomb is about to go off), it repeats several times, pauses and then repeats the noises. Only the second time I can hear clicking from all over the engine bay, at least four or five sources. My suspicion is that the computer itself is slowly going bad, and the clicking is it triggering the electric controls and sensors. I have one on order and should arrive by the end of the week. If the new electronic control module doesn't fix the problem, I'll be stumped. I would really appreciate any input!