I have a 91 5.0 when it's winter time I notice it more then summer if it even does it in the summer.

When I start it I have to keep my foot on the gas for about 2 min or else it will fluctuate and stall. After that it runs fine. The TPS was replaced 20,000 miles ago but the mechanic loved his junk yard parts so it could be that. The CEL comes on when driving but shuts right off. I don't have the thing to pull codes but it comes on when the truck runs fine.

Thanks

 

I've had my IAC (idle air cotrol) get stuck when its been this cold out and I would have to keep throttle till it warmed up enough to idle on its own or sometimes it does it all by itself.

I would try cleaning it with some brake clean and see if that helps.

 

You don't need anything special to check codes, just a paper clip, read the sticky thread on how to do it

 

Where is the IAC?

 

On the throttle body, looks like a cylinder with 2 bolts an wires.

 

And how do I clean it does it come apart to clean internally or just where it unbolts?

 

Just unfold it and be carefully with the gasket. Spray some parts cleaner inside to clear the carbon and boltb it back on.