i had a misfire in cyl #2 and lean condition on my 2001 4.2. lean condition could be PCV Valve, thats whats up with mine, the misfire on mine was fixed by a new coil... one shop told me lean condition could also be the upper intake gaskets/bolts.. just some ideas.

 

You have a valve train problem. Maybe a wiped lobe or broken spring.

 

Took the truck to the dealer this afternoon . THey hooked a computer up to it and we went for a drive .. Hit WOT several times . according to the computer 4 cylinders were missfiring especially #2. Changed ou the plugs ( no broken ones) then they found one coil was weak and so that will be replaced. tomorrow they will test injectors and test again to see if all is well. $268 for the plugs/ $180for the coil... smooth running f150 priceless

 

update to earlier post they changed one injector that had a slight lead down ... runs like new

 

Well, I just caught the "WOT misfire" bug a couple of mornings ago. WHipped out to pass on a 2 lane blacktop and it sounded like my truck was coming apart.

Same symptoms as everyone else, only does it at WOT when it downshifts. Goes away in a few seconds and takes off or can be cured by easing off on throttle.

Took it straight to dealer and was getting misfire on #1 Cylinder and then they got misfires on most if not all of the cylinders. Said it might be bad gas and sent me home with it.

Of course, he said it could also be plugs (which was his original thought when it was just misfiring on #1), coils or coil packs.

Fuel filter is way overdue to be changed, so I am gonna do that just for grins and see if it helps.

Stinks to have to throw a bunch of money into a problem that only happens at WOT.

 

Well I'm glad to see that I'm not the only one with this problem. I also have an 05 screw witht the 5.4. I'm at the dealer right now to see what the problem is. I have the extended warranty as well, so hopefully it will all be covered. I'll let everyone know what the dealer tells me in a little while.

 

My extended warranty expired 3500 miles before the problem started!!!!

Let me know what the dealer says.

 

Sorry I haven't got back on here sooner, but Ive been busy. Anyways, sounds like my dealer is just as ignorant as everyone elses with this problem. They told me it was bc of my k&n filter had fell off the cold air intake, but I called bs as soon as they said that. Anyways since they said it wasent a warranty issue I had to pay 90 bucks for nothing basically. They did reflash the computer but that didn't do anything. They said if it still was doing it I could have the mechanic ride with me when I come back in. So, tomorrow I'm going back and I'm gonna have the mechanic ride with me and hopefully they will go ahead and replace the coil packs or whatever the case may be. I'll let everyone know how it goes tomorrow.