86 fiero gt idle

[Athompson]

My engine idle lopes up and down about 50 to 100 rpm. Have any ideas?

 

[Oreif]

Idle lope can be caused by a MAP sensor going bad, dirty IAC valve, or a vacuum leak. Odds are it is a vacuum leak. Check the EGR tube that runs from the EGR to the upper plenum. These are commonly known to crack over time. If this is the problem, make sure you buy one for a 1988 Fiero V-6. They are made with a flexible tube and do not crack as easily. You can buy them at www.fierostore.com