I have a 2001 F-250SD with the 5.4, 5sp manual and 72,000mi. If I lug the engine down at all when I take off from a stop the truck will want to idle at 1500rpm until I come to a complete stop. The truck normally idles at 1000rpm which I thought was high but I have never ridden in another gas SD with a manual so I don't know what it's supposed to be, the autos I've been in idle around 750 or so. Of course when I'm driving down the road I don't notice a difference, not in the power or acceleration or anything it just makes it really clunky when I shift and when I come up to a stop when I push the clutch in it idles at 1500 untill I come to a complete stop, if it is still rolling any amount at all it will still hang up there untill the truck has stopped. I'm kind of clueless on what would cause this so any help would be greatly appriciated. It's been doing this for around 24,000 miles now so it hasn't really bothered me that much but ya know I think I might want to do something about it. By the way, my brothers '04 F-350 PSD just crapped out it's turbo, kinda makes me glad I have a gas.

 

the exhaust manifold on my 01 f250 5.4 is leaking and apparently
is causing the idle to fluxuate it goes from about 600-1100rpm
I dont know if that might apply to ur situation at all

Ive also had a 5spd car that would idle high like you describe
with the clutch in--it did throw a code though--it was the
clutch switch-- I replaced it and it idled normal

g/l

 

On the 4.6 and 5.4 motors, They have a thing called the Idle Air Control Valve. Which have been known to cause idle or stalling problems... Try taking it off and cleaning it w/ carb. cleaner..
Btw...My truck idles at about 600 rpm or so in Drive

 

I have an '04 manual acting very similarly. I took it to the dealer today to make them aware of the problem and to make an appointment to have it fixed. The first thought the service manager had was the idle air control. I'm heading to the Outer Banks for some fun this weekend but have an appointment for next Wednesday. I'll post the outcome then. BTW, when it does calm down 750 is the rpm.

 

My 1997 4.6 man did this same thing. At first I thought maybe it was a feature and was normal. Then I pulled off and cleaned the IAC and the throat where the EGR comes in (not sure what its called) with carb cleaner. I doesn't do it anymore so must not be normal.

 

This weekend I'm going to try taking the IAC out and cleaning it, during the week I really don't have time. But like Brianas and most 5.4's I also have a leaky exhaust manifold but that's no big suprise to most. Thanks for the help, I'll let ya know what happens after this weekend, if that doesn't fix it I'm going to have to wait till I'm out of school for the semister, and my brother's PSD finally get's straightened around so I can take it to the dealer.

 

Well this weekend didn't have time to tear it apart, maybe I will next weekend, who knows but like I said before thanks for all the advice.