my dad has a 97 expedition with the 5.4 triton. everyonce in a while when he starts it when it is pretty cold outside (in the teens) it starts and goes directly to low idle. it does not die but does not use high idle. it is after it has sat for a while, at least all day. i don't know what could cause this. has anyone else experienced this?

 

Sounds like a failing IAC. It's easy to change. (Idle Air Control) valve.

 

that is what i thought but i was unable to find it the engine. i cleaned it all the time on my 93 but i can't find it on the 97. the only thing on the side of the throttle body was the throttle position sensor. i will have to reinvestigate.

 

It's on top of the intake behind the TB Just under the cowl.