Re: excessively high idle?
If I remember correctly, the IAC valve(idle air control) has something to do with the trucks idle, hence the name. If you are standing in front of the engine, it is located on the left side bedind the tbi. It is known to get covered with carbon and all kinds of soot, possibly leading to bad idle, which can be easily cleaned with the proper cleaner. I like to use 3M throttle plate and intake cleaner every once in awhile, works great.You can use it on the IAC valve too.
"Don't you think this outlaw
bit's done got out of hand"---W.Jennings