Hi,

Reading your post takes me back to year 2000 when I first bought my 1991 volvo 940GLE, 16 valve. After sending the car for a check-up and service at one of the repair shop the car idle badly and it would stall. Whenever the car is on N or P the rev would increase to 1500 to 2000rpm (sometimes to 2500rpm) and it would cut out to 500rpm and it would rev back to 2000rpm. Its like the car is searching for idling. When shifted into D, then it would drop to 500rpm or sometimes to 800rpm and whenever I come to a stop at traffic lights, it would die out and I have to restart the car.

Sound like your problem is similar to mine (then). This is what I did. I took it to a volvo shop and I saw exactly what they did. They cleaned the idling motor, then they cleaned the throttle body. After that they check the butterfly's (the flap inside the throttle) position, and they adjusted the locknut then they re-adjusted the TPS (the earlier shop did a monkey's job),and the long rod that controls the throttle spool. They also checked the sparkplugs and mine was black, so they tuned the screw on the AMM and changed the plugs. That fixed the idling problem. So give it a go.

I hope your problem is only minor adjustments (especially the TPS) and will be solved and rather than something major is lurking under the hood.

velan
kuala lumpur,Malaysia.