engine revs to 2500 rpms after driving for 20-30 minutes on 2000 Ford Windstar

normally the car stays at 1500 rpms, but van will not stay there once engine is hot. It will not come back to normal until next day and engine has had time to cool completely. Please let me know the repair to make.

by in San Mateo, FL on April 13, 2009
1 answer
ANSWER by , April 15, 2009
You may well have a sticking idle air control valve (IACV) , possibly due to "dirt" accumulated in it's moving parts. I have been able to clean them as a fix in lieu of replacement.