Idle and acceleration problems [Archive] - Audi Forums

: Idle and acceleration problems

02-07-2012, 06:48 PM
My 1990 Audi 90 20V has issues idling and accelerating.

The idle issue consist of the idle jumping between 1200 and 700. When idling at 900-700 it runs like **** and sometimes bogs down even lower and stalls. I have changed the plugs distributor rotor and soaked the IVS in contact cleaner. Still no go.

The acceleration issue happens randomly when I'm driving. The car just loose power and the only way to make the car go faster is pumping the gas pedal.

This sucks. Any detailed help? I'm a hobie mechanic, try my best.

02-08-2012, 10:46 PM
you should try this site as it has lots of detail for your engine.

02-09-2012, 06:46 PM
I have a 2.3 L 80 quattro 5 cylinder. I have had 3 audis. Know them well. Check the hoses under your intake. There is a hose that goes to the idle stabilizer. The bottom of that hose can wear away over the years and you'll never see it. Also check the vacuum lines everywhere and listen for vacuum hisses. The is one toward the back near the firewall on the left side of the head cover and down in between. Again a hose goes to it and it usally a 3 way plastic piece that can have a small crack. Cost me $200 or so for Audi to find that. My car was running sporadcally and even shutting over with no symptoms right on the highway. Very dangerous. Couldn't find it for the life of me! Those are pretty cheap fixes. Audi has the hoses. Not too expensive or get online.

02-10-2012, 01:32 AM
My1990audi90...hi and welcome to the forums first off. If you have changed all those components you mentioned that's good, but all you've done is improved spark. Now it's time to look at fuel components. Try changing the fuel filter and see what happens. It could be as simple as a clogged fuel filter. Also if pumping the gas pedal makes the car go faster then I would also suspect a bad or on it's way out O2 sensor. Goodluck and post back.