92 Bonneville problem

[Alpha One]

This 92 Bonneville I was thinking to buy has a problem. It starts fine but then, in several seconds, it stalls. Sometimes it works for about ten seconds. If I press the accelerator a quarter of the way down or so it will keep running but accelerates and decelerates. well, it wants to stall. I was told that, when it started having the problem, the car would be going OK, then accelerate and stall. It would work in idle, but not anymore. Any idea what it could be?

I used a Actron Scan Tool and it didn’t show any error codes in memory, but when I used the Record Data function and then played it back it showed Quad Driver 1 Bad and Quad Driver 2 Bad. Does this mean the PCM is bad?

Thank you

Tony

[LMP]

Can you tell which DTC numbers that was? Probably something in the fifties ...
Quad driver errors generally relate to problems with the device that is connected to the driver. The drivers are internally short circuit protected .
With your symptoms, and the fact that quad drivers are related to EGR valve sections, I,d suspect EGR valve is the culprit. My first simple test would be to disconnect the connector to the EGR valve and see what happens.....
2nd, I've seen similar symptoms recently where the problem was caused by a blown so called "ign" fuse that is in the convenience center, not in the fuse block. With that, the a/c would not work, and neither the cruise, the evaporative purge valve and the O2 sensors.....all combined together it was all of a mess. Once fuse was replaced (it had been blown by faulty A/C clutch), all came back to normal within a few engine cycles.

[Alpha One]

The tool didn't show any error code number because it said there weren't any error codes reported by the ECM. I saw the message Quad Driver 1 and Quad 2 bad when I played back data obtained by the Record Data function which is recorded by the tool for 20 seconds or so and then you can look throug it and it shows lots of stuf like water temperature, spark advance, cylinder that missfired, or not, etc.

[Alpha One]

I forgot to say that the car works OK when cold. Once the engine warms up it stalls. The warmer it is the quicker it stalls. If the day is warm, then, it starts to stall in a minute, maybe less. I think the ambient temperature has to be at or blow freezing for the car to work for some time, maybe 10, 15 minutes or so.

Tony

[Alpha One]

I have good news (for myself . The Bonneville is working fine. I took it to an AAMCO shop and they said it was the transmission and it had to be rebuilt or replaced, it was messedup and in the wrong gear, and they did drive it around the block. Because it didn't make sent to me since it worked OK when cold, I went to another transmission shop, kind of a family shop, I didn't take the car because I didn't want to force it anymore. I just described what the car was doing and the guy told me to check the computer. So, I went to a junk yard and got a used one, $75.00, and replaced it. The car is working fine now. I drove it for about 45 minutes and no problem. I don't have much doubt that it is OK, I will see in the next few weeks.

I did put back the old computer and it does have a problem. Now, I think this is important, in my experiments I discovered that if the battery in the car is low, the problem is much severe. When I put a battery that I charged during the night, the car did hesitate etc. but the transmission didn't feel like dragging a heavy load.

Tony