Misfire and ticking noise combined. HELP!
 

Not trying to beat a dead horse here but i have been chasing this issue for months now. I bought an 05 F-150 FX4 with 5.4 in July in Colorado, towing a trailer back to California, every time i hit a hill or tried to pass someone under hard acceleration my tuck would misfire hesitate and RPM's would drop. CEL would flash on and off and eventually go away. Got a Cylinder #2 misfire code. I already did a tune up including all new motorcraft plugs, fuel filter, and new injector and coil pack on #2 cylinder. It seemed to help but now the truck is idling rough, still missing and hesitating under hard acceleration and gas mileage has gotten horrific! It is also making a horrible ticking noise on passenger side top end. not really a knock just a really bad tick. i have read about the cam phasers but not sure if that would cause a misfire also. I am leaning towrds possible phasers or bad lifter or valve spring. Anyone had similar issues all at once and discovered a solution? any help is much appreciated!

Coil on plug problem?

http://tinyurl.com/bpjm5et

it has a brand new COP and when i switch them to another cylinder it doesnt change. That's what has me concerned that it may be a rocker arm or valve spring or cam phaser issue. but i haven't heard anyone else having misfire issues with the cam phasers. i might just have to take it apart and see what i can find. not what i want to do but i may have no choice.

Have you done a compression test?

the dealership did one and said everything passed the compression test and cylinder balance pressure test. so i am kind of at a loss.

I have an 05 King Ranch 2wd w/5.4 doing the same thing. Havent changed plugs yet due the known issue removing old plugs. The CEL comes and goes, gas milage averages 14mpg. Under hard acceleration it misfires as if the rev limiter is kicking in an out. Not sure where to start since this thread doesnt seem to list the resolution yet. Watching :)

I have a 05 lariat and having the same problems. Found fouled plug cyl 5. Replaced and ran good for a few months. Back to missing under heavy throtle. Hooking up to a ford computer program Monday that maps the ignition while driving to locate where the misfire is now.

If you have a tick in the top end and it is not the phasers or injectors making the noise, you could have a lifter or valve making enough noise to cause the knock sensors to retard the timing to save the motor. you can unplug the knock sensors and test drive it again. If it runs right after disconecting the sensors your problem is not in the ignition system but mechanical.

I have an 04 with the 5.4 and i am having the same problem but mine isn't under hard acceleration it is between 40-50mph at 1100 rpm it is missing very hard to the point where the whole truck shakes. My check engine light would come on and i would get a #2 misfire and bank 1 running lean. I have replaced the following: o2 sensor on bank 1 sensor 1, ignition coil and fuel injector on #2 and i am still having the same problems. The 2 things i have left to try is spark plugs and vaccum test. Hope somebody can come up with an idea.

Thanks for that Karl. I will try first chance I get. my plugs are due so I will do one thing at a time and check back