Misfire Counts On All Cylinders

[RoushSTG2]

Been having these same issues going on 2 years now and have replaced everything I can think of, done multiple crank relearns, read probably every forum covering any sort of misfires, and i’m still having these issues. Was just curious if you ever figured out what was causing your issues and if it could’ve been those o2s.

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[Ishyne22]

I know its been a while here… But do any of you have any data logs of fuel trims?? Probably the most important info in diagnosing problems is fuel trims. Did any of yall do oil pump gear installs? It is still quite possible to be “off a tooth” on your timing. Which would cause misfires on all cylinders. Second, The cam phasers on late model 5.0s are notorious for failing. These phasers actively change maps by adjusting cam angles using oil pressure. If oil pressure is weak or cam phasers have debris in them they do not function properly and create misfires and rough idling even more evident at idle.. Ross

 

[Fat_Joe]

Update on this thread, but I unfortunately got rid of this car as I could not figure this issue out and it was driving me crazy

 

[Epiphany]

I feel deprived of what I thought was going to a unique solution. Drats!

 

[acemastr]

I had a similar thing recently, chasing misfires between 2-3k rpm. I spent months replacing and data logging everything. Took it to ford and they diagnosed cylinder pitting and scoring. Just got a new engine installed. This is with a meticulously maintained engine, oil changes at 5k, plugs, always warmed up. I just got a bad one I guess, took 62k miles to figure it out though.

 

[Epiphany]

Took it to ford and they diagnosed cylinder pitting and scoring.

How did that correlate to misfires? Was compression low in certain cylinders?

 

[acemastr]

How did that correlate to misfires? Was compression low in certain cylinders?

Yeah, plus a valve guide issue on 5. I wish I knew what caused it, the ford tech was actually a good guy and walked me through everything but he wasn't able to give a definitive answer other than low compression. Funny thing is it was fine at wot

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