fyujm20

The idle surges up and down, up and down. Eventually it will kill on a down surge and may not restart. I have spent $750 at 2 shops and still don't know what is wrong. 1st shop replaced the computer(used)...no luck. 2nd shop replaced the air flow meter(potentiometer)(also used)-again no luck. Their next step is to dig into the wiring which could be even more costly. They say the idle stabilizer valve is okay.
What could be wrong with this thing?
Anybody have a clue or suggestion.
Thanks,
Jim

QCRAZY

How long ago was it that you changed plugs, air filter, fuel filter, cap and rotor?? If it's been a while that is always the first place to start.

Judging by the year of the car I would also suggest you replace the spark plug wires. That gets you to a starting point. From there you can start looking for problems (if they still exist).

If all the above has been repalced and you are still having trouble then you need to check for vacuum leaks. Then go out from there...

Kidquattro

I had the same problem with my `88 5kqt. I thought it might have been the O2 sensor but i had my mechanic check it out. They pulled the codes and the fuel mixture was off. The car runs mint now. Any shop that replaces the computer has no idea what they're doing. That would be the last think to check. I would try to find a good Audi mechanic. Where are you from?

ginutz

Have you checked all your vacuum hoses...there are many and its the easiest check and fix.

audiqv8

Pull the DTC (Diagnostic Trouble Code). You should be able to blink it out.