Ever since it has started to get cold I have had an odd high idle issue. The truck is a 92 F250 351W E4OD 4x4. Even after the truck is up to operating temp it wants to idle between 1050 - 1200 RPM. If you shut the truck off and restart it the truck will resume normal warm idle at about 700 RPM. The CEL is not on, and there are not stored codes.

Any one have any idea what could be causing this?

matt

 

IAC likely is dirty or just needs to be replaced