Idle Air Control

TWF_John

I received a question from a feature car owner on his car:

My fast idle when cold stopped working recently. I am guessing that the Idle Air Control isn't working properly even tho it is clean and free to move. I talked to CJ Pony's service department and they said if you start engine when cold and turn on the A/C, the idle should increase if the IAC is working properly. I tried it and it doesn't increase the idle speed. Have you had any experience with this?

Unforunately, I rarely run my A/C and when I do it is usually after my car is warmed up in order to keep it in good working order. So, I don't have any first hand experience with it and a cold idle. Anyone have any thoughts?

jkupka

Tell him to use this link. I used it on my 95 (F150) 4.9 and it worked. Ford trouble shooting guides are usually extremal close for each year.

http://www.ford-trucks.com/forums/13453 ... stion.html

TWF_John

That is a good thread. I heard back from him last night and it looks like he got it straightened out:

It turned out the Idle Air Control was the problem and when I installed it, the car ran worse. I sprayed starting fluid around all the vacuum lines and discovered the one under the upper intake was shot. The engine would speed up with each spray of starting fluid for a few seconds. After replacing the vacuum line it runs better than ever. CJPony Parts service dept was correct on the air conditioning test in this case. The plunger was fine in the old idle air but apparently the solenoid that controls the plunger goes bad.