1991Avant20V

Here is exactly what my car do everytime I drive it.... ( 1989 200 Turbo Quattro 5 spd, 180k miles)

1) Starts right up and idles at 1200rpm for 10 seconds

2) Idle drops to 750-800rpm after 10 seconds and the car sounds like it wants to die. Sometimes it drops to as low as 600rpm and dies..

3) When the car warms up it would sometimes idle at 1200rpm, sometimes at 1000rpm, and sometimes fluctuat a little between 800 and 1200rpm. If I gas it a little it would start fluctuating

4) Maximum boost is at 1.3bar

5) Engine speed seem to come down slowly from rev... weird...when I am shifting gears at 3500rpm(or any rpm) it would stay at 3500rpm for a split second after I let off the gas pedal and then come down in revs relatively slowly...

6) Tried to pull engine code by sticking the fuse in the fuel pump relay(new) but the check engine light does not come on. When I pull the fuse out, the engine would sometimes die..
Tried cleaning the ISV with carb clean...

Does anyone have similar problems?

Thanks for your time guys...

SteveAngry

Have you checked your intercooler to throttle body hose yet?

Your boost sounds low and you might have a vacum leak caused by a torn IC/TB hose...

Pull off the hose and inspect it carefully...

Just a guess.
Steve
Michigan

1991Avant20V

will give it a try...
Thanks

comp_jas

Should visit www.sjmautotechnik.com.

I thought you needed a test light for the 200's to pull codes. Check engine isn't used.???

comp_jas

1) Sticky ISV - easy to clean and re-try

2) Decel valve - more difficult and less likely

audiluver

I had vacumn leaks at the Michelin Man hose, last time I had something similar.