batts86

Hey, this is my first time posting on here. I have a 2008 F150 with the 5.4 and my truck really seems to have a lack of power especially from a stop and really anything before 4000rpm. Also sometimes when I take off it will just completely bog out on me and spit and sputter(so to speak). I have recently put in new fuel filter, fuel pump, fuel pump driver module, all 8 COP's and the spark plugs only have about 40K on them. Does anybody have any suggestions before I take it to a mechanic because I am stumped and really don't want to keep throwing parts at it. Its not throwing me any codes at all. Thanks guys.

bourgeois1269

Any modifications like big tires ?

ng8264723

Injectors?

Mod (Ret.)

Any stored diagnostic codes? If you don't have access to a OBD-II reader, take it to a good auto parts store; many will check your truck for free and give you the codes. Just refrain from buying the various parts they will suggest you buy to fix the problem(s) until you research more.
Post any found codes here.

techrep

iTrader: (1)

Check the foam gasket around your air box...clean throttle body and MAF ...do the throttle re-learn...

powerranger262

Could be your cats as well.

batts86

Hey guys thanks for the info, finally got a code...cylinder 6 misfire detected hopefully just a plug gone bad!

grss429

replace all plugs and boots/springs

Summers22

iTrader: (2)

But only do this with Motorcraft plugs and coils.......

Summers22

iTrader: (2)

1 bad plug shouldnt make it spit and sputter. You may have other issues like a clog cat as mentioned.