I just replaced the IAC motor and cleaned the throttle body.
Did this because of inconsistent idle...would rev itself up at stops and could even feel the truck pull itself forward at stop lights.
So now that I have a new IAC and clean TB it is a consistent idle, just very high. sits at about 2000 RPMs
I'm wondering if there is an idle relearn process or something like that to let the truck know how to idle properly.
Does it need to be reprogrammed by a dealer?

anyone know?
Sorry, I guess specs on the truck might help...2001 SLT 4.7L 2wd

 

I'd think a vacuum leak. Check everything again. Unwanted extra air means the computer will add gas to make it run smooth, which makes it go faster at 'idle'.

 

Thanks, I'll check again.
From what I did, the only piece I removed wad the iac. Maybe the butterfly may be stuck open a little. Know of an easy way to check for a vacuum leak with out any specialized tools?

 

can of carb cleaner, spray any suspect areas, if the engine speed changes its pulling in the extra fuel.

i have also heard of people using an unlit propane torch, but i wouldnt recommend that method myself.

 

I know this thread is a couple years old but had a similar problem on my 5.9 Magnum engine.

swapping the ECU solved it.

tried 3 different IAC including one from a known good engine. None would close so the RPM surges to 1500+.

$90 ECU from a boneyard today instantly solved it.