Why is my 1996 lincoln mark viii holding a high idle
4 Answers
Possible vacuum leak. Check vacuum lines and replace if dry or cracked. Possible vacuum leak at intake manifold or base of throttle body(if equipped).
Refer to the following link for detailed info: www.aa1car.com/library/vacleak.htm
My 96 Lincoln Mark VIII had a slow idle and it was the idle control motor. I took it off, and was it a hard one to get to also. I cleaned it with some Mass Air sensor cleaner and it idles ok now. Ive been told that the same motor controls the idle, when its too fast also. Hope this helps. It is a hard little controller to get off. It is beside the throttle body and I had to take that off too. It wasn't bad to get off.
One more thing to check is the alternator. I had a high idle when first srating the car (about 2100 rpm). After sitting for about 30 seconds, the idle would drop to about 1100 rpm. After about a 2 months of this, the alternator went out. I had strange symptoms with the alternator. About once a month the dash lights would dim for about 3 minutes and then come back to normal. After the alternator finally went out, I replaced that and the battery. Immediately my idle was back to normal.