Warm idle in park should always be between 700-750 rpm per Ford. BUT, these trucks idle very smooth, usually at 725/730 rpms. Outside of those numbers, somethings up. Below 700 can be IAC or somethings plugged up. Over an above is a leak or IAC. The programming will always attempt set idle. They really have to be messed up somewhere when unable to achieve.

 

Exactly. If you have a code reader that will read the IAC %, you might be able to tell if it's dirty (carbon) ports. I forget the correct percentage, but it seems like normal was around 35-40%.

 

lol ive said it before, not to be rude, but i bought this IAC valve 2 days ago, took back the other one that was only 30 days old and didnt help. So cant be iac valve

 

This has been said before so not to be rude but new parts don't automatically = working parts. New parts are DOA all the time...

 

^^^^ Especially Autozone parts

 

If that's the case, ignoring my post, not even questioning it, might be considered as utter stupidity.

 

Not to be rude, but you need to go back and read it again. The ports in the throttle body/housing, as Brew also mentioned, get dirty and full of carbon.

 

Jeezz Skylar

I'll pretend your cats are good and installed.

Take a good pic of the top the engine with the air intake connected.

Pull the air intake and take some shots of the top of the engine again. Good pics so we can see how your vac lines are connected. For the engine to idle THAT low, something isn't right. There's nothing else that would make it idle like that unless the PCM is toast.

Do that and prove to us you actually want to fix your problems.

 

Right, something has been overlooked.

 

Rude.....