I just bought a 89 f150 xlt lariet, and when i start it it idles at 3 grand. Ive checked all my vacuum lines. they seem to be ok. Has anyone had this problem and if so how did you fix it?
Check your idle speed control, it may have the plunger stuck open, also check minimum air rate, make sure someone hasn't cranked open the air valve in the throttle body.
idle air sensor
No such thing Colin. Tennisshoes is right on track with this one. You have a large amount of air getting into the engine. Other sources are the Power Brake Booster and PCV. It's a big vacuum leak and shouldn't be that hard to find. 2 bolts to pull the IAC, you can clean it with carb spray and carefully move the plunger to see if it's free. Is the "Check Engine" light on?
idle air sensor or idle speed control ive hear them called both on different occasions,anyway I do agee with tennisshoes my comment was not meant to contradict his anser.ive had that part let go on me several times when I was running those old fords.sometimes in a jam u can clean it and get a few extra months out of them.
Search Ford F-150 Questions
Ford F-150 Experts