Spudy

Hello all
Joined the forum with hopes of getting my f150 running right so i can enjoy it like everyone else does. I have a 2005 Ford f150 with a 5.4 auto.

It has a rough idle(shakes the truck), very little power, and poor gas mileage. Randomly It will throw a code for misfire on 1 and/or 3 on start up only. It does seem to perform better within the first few of starting but dies right off after that. In fact i got stuck in the snow the other day and it could barely break the tires loose to try and get it out (almost put in 4low cause i didn't want to hurt the trans)

I have replaced:
Cats
Fuel pump
Plugs (motorcraft)
Random Coils
Did the timing chains and phasers
MAF
All new injectors
Intake gasket

Was at my mechanics and had a scanner on it and at idle the 1-4 cylinders are all show a negative cylinder contribution. But when you rev it up they all go to 0 across the board.

Was kind of thinking about the Variable Timing solenoid.

Any advice would be greatly appreciated.

ak_cowboy

I would replace all the COPS. Also look at the FPCM above the spare tire. Are you stock, or do you have some mod?

corey_lax

FPDM, fuel filter, Air filter, is where I would start. Cheap, easy and regular maintenance, then move on to the more expensive stuff.

Spudy

I have replaced the FPCM above the spare, did fuel filter and have put an cold air intake on. I do have a preditor programer but i dont have it installed as this time to help narrow it down.

TomB275

Plug wires.

rubbinsracin

There are no plug wire so to speak. could be the COPs but it sounds as you have replaced some of them.

I was having trouble with a misfires on 1 & 3 after a plug change and pulled all the COPs back off and double checked that the plugs were tight and they had worked loose shlightly.

when you replaced the plugs did you put dielectric grease in the tip of the COP? after I tightened the plugs I did this and was amazed at how smooth the idle was.