Everyone must have read all the problems I am having with this truck and surging on a warm idle. Wow do alot of people have this problem!!!!! I am glad to say that with the help from Frank (Fmr9) the problem is solved. on my other post you will see that I tryed every sensor,checked every vacuum line,checked vacuum 100s of times and still no end,still surged. Frank told me to try Ford Idle Air Adjuster Kit for '86-93,part# F2PZ9F939A that he had used on his truck.So after all hunting around I found a stealer(dealer) who had one 1hr away.I made the trip and within 10 mins the truck has never idle and ran so smooth in its life.You could rest a coffee on the intake at idle.Isnt that crazy for one of our beloved Ford trucks. This kit is an absolute must for all our trucks.Dont even hesitate.I paid 70$ cdn.and I will never look back.Thanks again to Frank and all you other guys. Thanks

 

What does this kit look like and how does it work exactly??

 

what if you have a 94-96?

 

I googled the part number and got several hits. The kit makes the idle speed adjustable and fits between the throttle body and the IAC housing.

http://k-mansparts.com/items/f-150/f...39a-detail.htm

 

Wow that could be a fix for my truck. It wants to idel too high. I am going to try to clean the idel controll valve first.

 

In the instruction that came with the kit it said is was design so that the IAC doesnt need to be cleaned. In the instruction it also says not to clean the IAC,but we all do anyways,as I did. The kit comes with a plate that has adjustable screws for the amount of air that enters by the IAC.Its great have you can change idle rpm just by moving a couple of screws. As far as years and models,it is for anything with that design IAC. In the instructions it list 5.0L any year,5.8L and 7.5L.Trust me guys I am still shaking my head on the difference it made.I actually like hearing that old 5.0 purrrrrr like a kitten at idle.

 

Hey Hog Hauler
I'm glad it worked for you. Difference is amazing isn't it?
Frank

 

this sounds like a band aid fix.

i read the link and it seems to me to just replace the iac would be better.

 

THe surging idle problem may not even be TPS or IAC related, on my 90 it was a stuck AIR diverter valve that was only injecting air at the heads, and not switching to after the first cat, 02 saw all that extra air as lean, so it was running bigtime rich trying to compensate... Had the rolling idle, horrible gas mileage, and white smoke out the exhaust.

 

I completed all the test that old paint explained to do.Everyone who owns one of these trucks should buy a vacuum gauge.Did it ever help.I did replace the IAC and still had the warm surge. I was ready to take the intake manifold off as that was the last place to find any leaks. I wonder if nothing was really wrong because when the truck started it would have 20" of vacuum and would hold that for 15 min until it was good and warm,then it would surge. My vacuum would then begin to go up and down.Glad I listen to the guys that told me to get the IAC bypass. Does anyone else think this is funny that FORD brought out this fix.
https://www.ford-trucks.com/forums/6...e-surging.html

 

owning a vacuum gauge is a must if you are a serious vehicle tinkerer.

 

I have a vacuum gauge mounted on my dash. Not only a diagnostic tool but good for gas mileage.
regards and Happy New Year
rikard

 

I remember seeing an old chevy Caprice with a vacum gauge for gas milage. I guess it works for keeping your foot out of it.