I have a 2003 f-150 5.4 with 205000 thousand miles. I have a misfire in cylinder 2. The past 10 k miles i replaced the spark plugs,coil,fuel filer. The injector works ( screwdriver you can hear it tick and unplugged truck idles down). I'm pretty stumped what the problem could be. Thank you.

 

Assuming you actually have a misfire code, since you didn't say that.....

Did you replace a spark plug and coil with motorcraft?

it's easy to swap spark plugs, coil, injector, one at a time with another non- misfiring cyl to identify if one of those is the problem without spending a dime.

If, after doing that you still have a number 2 misfire , you will need to start checking compression, and looking for a manifold leak well as the signals to the coil and injector need to be verified to be okay .

 

yeah i think it was p0305

 

PO305 is cylinder 5.

You might want to rescan it and post the actual codes

 

po302

 

That is cylinder two. Easy to access.

switch the coil with cylinder 1 and see if the problem moves.

 

weirdest thing. I changed the coil and it ran so smooth for about 20 minutes and then it started misfiring again.

 

ok. Now is there a DTC? Where is the misfire now?

 

Were either of the coils wet or oily when you pulled them out?

 

Yea, they can do that for a short time after reset. Normal. But yea, doesn't last long.