High idle on 5.0L HO engine

cleaner, re-installed it. No change, still idles at 2000 rpm.

try it. Since I can't , I thought I come on line and ask first.

might have a vacuum leak ? check the hoses. Remove NO-SPAM from email address when replying

I,ve been looking for a vacuum leak. I took a propane torch, opened the valve and used the gas, putting it by = everything I could find. No increase in idle.

Here is what I just got done doing.

I hooked an ohm meter up to the TPS sensor, not the wiring harness, the = TPS sensor itself. On one end and the center I have .87 ohms at idle = (Engine off during this) increasing to 4.1K ohms at WOT. As I increase = throttle the ohms go up . I hooked it from the center to the other end = terminal. 3.6K reading at idle and .37 ohms at WOT. I then hooked it to = both end terminals and got 4.34K ohms no matter where the throttle was.

Would this simply test rule out the TPS?

How can I check the IAC to make sure it is work>=20

with carb cleaner, re-installed it. No change, still idles at 2000 rpm.

buy one and try it. Since I can't , I thought I come on line and ask = first.

A word of advise on Fords IAC's The Idle Air Controls use an accordion type diaphragm, these quite often develop cracks due to fatigue from the constant in out movement and will cause an extremely high idle.

TIM -aka- MUSTTANGUY "at" AOL "dot" COM

Hook up a code scanner and scan the computer for codes. If you do not have one visit your local auto parts store as they may be able to read the codes for you.

Fix any codes if you have them, it may cure your problem.

Has it always idled high or did this just start?

Today is Sunday and the parts places are closed. Otherwise I'd just buy one and try it. Since I can't , I thought I come on line and ask first.

What do you think?

Dan

It started all of a sudden. I have a code reader. With KOEO it gives me 33. Something with EGR. With engine running it gives me 412. Can't adjust idle for tests ! If I push against the EGR spring bellows when it is running, the idle = will slow down. I don't know if it is because it is then running on = recirculated gases or if that is the problem. The spring is pretty stiff = to hold in.

Someone mentioned weak bellows in IAC. While cleaning I did see some = thin beige material come out of there. All I saw was two springs. One = small and one bigger. The bigger one is where the material came out of. = Perhaps this is my problem. Is there any way to check this thing? Can I remove it cover the holes in = intake and start it up? Possible make a temporary gasket with no holes = for spring windows and reinstall then start up?

Any thoughts?

Dan

I just got off the phone with a Ford mechanic friend. With all your info considered, he says it's the IAC. They cannot be serviced. Parts stores should have them for about 40 bucks, or go to Ford tomorrow. Good luck.

CobraJet

I have a Fox IAC in good shape if you need it, email me. KJ

snipped-for-privacy@hotmail.com seems to work. KJ

Sounds as though you found your problem, Super !!!!

TIM -aka- MUSTTANGUY "at" AOL "dot" COM