I Have the same problem, just replaced the IAC, and it didnt do a thing. The truck drives great but does the same rough idle as your truck does. Mine only has 22,000 miles on it. Ford is not any help either Ive been back and forth with them, I think I might just give up and live with it until I can buy a new truck.

 

I'm going to continue to fight with Ford on this, I'm so tired of getting screwed by Ford. I've been screwed by Ford since 1991, I swore I would not buy another Ford, but I think their trucks are better than Chevy or Dodge, I hate to do it but the next truck may be a Nissan or Toyota. I will keep eveyone updated on the battle with Ford.

 

definately not normal, that's Fords explanation for everything they can't diagnose or fix.

 

Interesting thread. My '03 SCREW 5.4L with under 10K miles also has a rough idle at times (more of miss type as opposed to a surge or a vibration). My old '98 Expy 5.4L ilded smoooth but did not have nearly the power/acceleration of this new engine. If the price of the power is a little aggravation with a rough idle, I'll live with it. I wondered if the engine just wants a bit more octane than the cheapy stuff I usually feed it but sounds like others have changed fuel and not seen a difference. Everything else on mine is very new so I assume in good shape.
As I understand, Ford made some major upgrades to the heads/cams on the newer engines vs my old '98 and are running on the ragged edge of what it takes to maintain a silky smooth idle. All in the name of extra ponies, which is a good thing .
A friend of mine is a Chrysler/Jeep tech and he said they have the same idle issues on many of their newer motors. My wifes '04 Sebring does the same every now and then. Is this the new age of motors? If we can't have a smooth idle, at least give us a good sounding exhaust to go with the lumpy idle

 

after my trip with ford the idle is better but not perfect.It is still cool.Like cowman said a little ruogh idle is o.k. if all else on the truck is good.I love my f-150 and the 5.4 seems to be able to get it on!!!so I am satisfied with a little quirk as long as it is minor.Stay cool my fellow Ford drivers.

 

There are some interesting threads here for sure. I have a couple of observations

1 If anyone here test drove their vehicles and it's idle was rough or surged you never would have bought it correct. So the conclusion here is that in most cases this problem shows itself after .xxx miles. In my case about 9k.

2 The surging is something very diffrent. I got a letter from Ford a few weeks ago saying they are pleased to extend the warranty (2 more years) on part # 9J460 Tube Mounted EGR Pressure Sensor. I called 1 800 Got-No-Clue and after a little discussion was told one of the indications the part is bad is 'Engine Surging". Ford says only will replace if bad I asked how I find out if it is bad. The reply was bring it in and pay a diagnoses fee $75 to check. I asked why not just do a recall if you know it is a part which is poorly made but of course no answer for this.

3 93 Octane fuel will not fix this at all so save your hard earned cash. Point of fact is that you need to adjust the timing in order for the truck to run on 93 else detonation.

4 The get used to it idea is ok IF YOU CAN . But when you pay Thirty Something for a vehicle you should expect the parent company to take a interest in seeing customers satisfied. Ford at this point absolutely has no interest in this concept. Witness the mess they are in with their technicians cutting back allowed times to complete on warranty claims. In some cases causing the dealers to cut corners o rsimply skip the repair.

Happy Motoring

02 F150 FX4 4.6
Flownmaster
K&N
Custom Tuned

 

Mine has done it since I bought it, and so have a few others that I have been in. It is a combonation of the cam timing and the lean fuel mixtures at an idle that cause this. It is a bit annoying but doesn't hurt a thing. My 88 5.0 Stang has done it since I bought it new. They just run the idle mixture as lean as possible to keep emmisions down.
A carbureted engine will do the same thing if you lean out the idle mixture.
It's all part of the EPA trying to keep the air we breathe a little cleaner.

 

John the sensor that you got the letter from Ford about is the DPFE which you have probably seen mentioned on here lots.
Unless the Check Engine light comes on it is probably working ok.
Usually if the DPFE causes a surge it is at cruise speed. A bad DPFE doesn't tell the PCM what the EGR is really doing so the PCM opens the EGR some more and that causes a surge. At idle the EGR should stay closed.

 

This whole idle quality issue has me watching my idle much closer now or the idle is getting worse. Either way I am noticing it more when it occurs and also noticing when it is smooth. The odd thing is on any given trip (or stop light) the idle can be rough or smooth as butter. So I assume the cause is not mechanical but more likely fuel or programming related. As I am now over the 10k mile mark and the problem is getting more noticable, it makes me wonder what the idle quality will be like in a year or two. It is getting to be irritating and hopefully Ford will come up with a fix. Meanwhile I will be making an appointment at the dealer to get the problem lgged in and checked out. I really don't expect much as this seems to have been going on for some time now. Hopefully Ford is putting some effort into it.

 

hey guys my 01 5.4L s-crew 87,000 miles does'nt vibrate but i had a 4.6L cougar that did it at idle and was in the shop lots, the service manager told me the computer wanted to know why the car was'nt moving and was turning sensors on and off to check if everything was ok. that sounded like bs but they replaced everything under warranty and could'nt get it to stop so we accepted the theory.

 

hmmm that's one I haven't heard before

 

good one huh? he kept a straight face the whole time.
mike
01 4x4 s-crew 5.4L 87,000 miles

 

This was happening to me on my 1998 f150 5.4L and I just cleaned the IAC and no problems since!

 

Hi Jimmy/Dave

I am sure that this idle thing will cause no harm. I am just as sure that it will annoy me right outta Fords sorry to say. I have been a Ford owner for 35 years.
Jimmy if it is a idle mixture,cam timing issue why cant a program be developed so that for those who are unhappy with it can have it fixed. By the amount of threads here the number of unhappy customers is many. Dave thanks for the clarification I am not seeing any check engine in fact the computer has no codes logged at all. Sorry If I sound like a whiner but the idle is really getting to me.


John

 

I hate to say it but I feel thew same way as you. My 2002 is my 5th Ford truck with only 22,000 miles, I cant stand the rough idling any more.