Saab idle, 1998 900 manual turbo

Ok, my engine light is on & the mechanics I’ve tried cannot solve the issue.

The current code signals a problem with the idle, but the mechanic does not know how to fix it. The car does not smell good when it is running-- it smells like the fuel is not burning properly, maybe like oil.

It used to be adjusting an idle was very easy, but I guess times have changed.

Any suggestions?


Are you taking the car to a mechanic who specializes in Saab? What have the mechanics tried, so far, to fix the idle issue?

The garage claims & has a reputation for knowing how to work with saabs. It is not a saab dealership.

They seem to be stumped on the issue. As far as I understand, they (& another mechanic we tried) think the idle is controlled via some kind of electronic component (perhaps the on board computer or drive train?) and that this electronic control can’t really be fixed without changing out the computer.

If you know more about the subject, I’d love to hear it.

More information about what my mechanic has done:
he has worked on the throttle body, but this has not helped. He has looked for other things, but can’t find what is wrong.

The code for random misfire is also coming on.

most likely it is sensors and not the computer that is the problem. There are sensors for engine speed, for air flow, for exhaust 02, and any one of them could be the problem. Your mixture is too rich, and that is why you are getting a fuel smell, and is likely the cause of the missfires as well. But have them check the timing with a light, just to make sure it is not a timing problem as well.

Since this could be caused by any one of a number of things you need to take the car and have AutoZone, Advance, Checkers, etc. scan the car for codes. They will do this free.
Post any codes back for discussion and this will at least give everyone a starting point to figure this out.

Making a very wild guess based on ragged running and this smell you mention I might take a stab at a leaking fuel pressure regulator but that’s grabbing something out of the air.