Hello everyone,
This is my first time and post on this forum. I've been having issues finding answers online so figured I'd ask directly. Lately my truck has been idling strangely where it would do one of three things:
1) Idle high
2) Idle low to a bog
3) Leap forward when stopped
I believe it to be either idle air control valve, throttle position sensor or MAP sensor. I've been doing some research and thinking possibly something to do with Intake Air Temperature sensor? It seems to me like they can all contribute to abnormal idle but can't determine which is the culprit. Its been cold lately which may contribute to the issue. Any idea would be greatly appreciated. Thanks!

1992 F250
5.8L Windsor
110,000 miles

 

There is a way to check for any codes, but from what you describe, my first choice would be the IAC (Idle air Control). If it is all carboned up it will have problems working correctly . They did not recommend cleaning them because certain ones had a protective coating and cleaning them removed that and left problems.
If you can't get the correct one from Ford (per vin) at least get the part # and go from there.