I have another idle question. It seems everyone has an idle problem with their 5.4, but mine is with my 94' 5.0. The idle runs smooth; however, it will jump from about 900k to 2.4k and back down. This is really bad when it is cold outside even after it has ran for 10-15 minutes. I have disconnected the neg cable to reset the computer but no change.
Does anyone have any other suggestion? This seems to be a diffferent problem from everyone else's bad idle on the board.
Thanks

 

When was the last time you replaced your PCV valve? If you have replaced it recently, sounds like a vacuum problem to me.

 

I had an idle problem with my 99XLT extended cab. The dealer found that it was the "throtle position scensor", it was replaced under warenty, no problems. But for them to find what the problem was, I had to get to the Dealer while the idle was up and keep the truck running so the Tech could get his gear plugged into the truck. I hope this will help.

 

I just bought the truck a couple of months ago, so I don't know it the PVC valve has ever been changed. Sounds like a good place to start before I take it in to have it ran on the machine. Thanks!