Questions and Answers

Olds High Idle

Q. I have a 1988 Olds 98 w/ 3800 engine and it idles too fast. It has 98,000 miles and I had this same problem about a week ago and I put a bottle of injector cleaner and the problem cleared up. This time it continues to idle too fast even after using the cleaner again. Any help??? Dewey

A. I don't see how the injector cleaner could help the high idle speed.

If the engine runs fine otherwise, I would look for a problem with Idle Speed Control (ISC) motor. This is something that is not easy to daignose without special equipment. A shop with a scan tool will be able to test it quickly and accurately.

One thing you can check for is vacuum leaks which would cause a high idle as well.