When you disable the idle speed motor you give up a lot. The motor will no longer run faster when cold and if you turn on the A/C or run a lot of accessories like headlights and rear defogger the ISM cannot keep the idle speed stable. Under high loads at idle the ISM will keep the idle at 775 rpm. The fixed metering screws cannot adjust to varying loads. In addition in some states you are not supposed to tamper with anything that can affect the emissions. Some states do check these things. For your own sake and that of a future owner it is usually best to keep the car as origional as you can. It is often harder to make changes than to try to stay origional. David Teitelbaum vin 10757 --- In dmcnews@xxxxxxxxxxxxxxx, "content22207" <brobertson@xxxx> wrote: > Mention this to list with trepidation because it usually ignites flame > war, but IMHO is important: > > At same time JZD was messing around with idle speed motors, Volvo just > used brass screws already built into PRV to set idle. Low tech, yes, > but less subject to problems. I think every owner should know how to > use in case automatic idle system fails or needs diagnosis, if