I think its time to sell this POS

[markNtennessee]

My 2001 EB 4x4 5.4l is acting up again. it has a miss at idle. I have replaced the plugs yesterday, went back to motorcraft from NGK. now most of the plugs looked horrible, some worse than others. on the passenger side all the plugs were white and the drivers side were ok except for the back one and it was white also, and they were less than a year old. i found what i thought was a bad coil pack, cause the bottom of the pack where the arrow is had a bid bubble on it, so i replaced it.

So far i have replaced the PVC hose, TB and upper intake gaskets, EGR gasket, cleaned out the TB and EGR port, replaced the plugs twice, went all over the engine with carb cleaner. starter fluid and propane looking for a vacuum leak. cleaned the IAC, MAF.

Im getting tired of this thing running bad, it dont seem to run all that bad when on the highway, but it does have a miss at idle.

Also hooked up a scan tool to it and no codes were present, but the LTFT on bank 1 was 10.8 and the bank 2 was 6.2 at idle, the STFT varied from -3 to +3 at idle. Now at 2500 rpms the LTFT went to 6.8 and bank 2 went to 0. I have no ldea how to read the fuel trims. so it seems theres a problem when looking at them, but i cant figure out what it may be.

 

[bring_em_on]

Have you tried replacing all the coils? Mine was acting up as well (although sounds like yours is worse) and my mechanic said that even though it's not throwing codes, the coils could still be degraded enough to cause problems. So I ordered a set of after markets from Uneek Supply and replaced all of them. She runs great now.

 

[jkill351]

my cop's started to fail at 60000. they would just randomly start to misfire. at first it was just a rough idle, then a flashing check engine light, then nothing, back to flashing, and finally a solid light. interestingly enough it would just clear itself up. so i just started checking all of my plugs and cops. my cop on #7 failed so badly that it caused detonation and melted the electrode in the new plug. if it had just dropped into my cylinder id have a new rebuilt 5.4 as the electrode would have scratched my cylinder badly and i hate blue smoke.

once i got sick enough of this i just replaced all of my cops with accell cop's i got from autoparts warehouse for less than 320 (huge savings over replacing 1 at a time with motorcraft cop's). also my throttle response is better with more hp and improved fuel econ. 1 other plus of accell is the yellow tops look good on the expy. i would recomend this to everyone.