I have a 2006 supercrew 5.4L 2wd with 80,000miles. I have had no problem with the truck except for now under hard acceleration it seems to stumble.
I have changes the fuel filter (factory motocraft) after it started but the problem was still there. I dont get a check engine light or anything. Could it be the plugs (never been changed) or the coils ? I thought I would get a check engine light if I had a misfire? I have not hooked a code reader to it yet due to the one I have is to old for this truck.

I appreciate any help before I take it to the dealer. Also I am a equipment mechanic so I can work on it myself but have never had to up until now.

Scott

 

check it for codes, clean your MAF, air filter and plan on changing plugs and maybe the cops

 

its the plugs no doubt about it my truck started doing that same thing and i just got the plugs changed them last weekend and the truck runs like it is brand new....

 

Thanks guys I will start saving up for them and possible the removal tool.

Scott