Martinisteve

Hi All
I have a 2012 Screw with the 5.0L, have 56000 miles. At around 50000 my check engine light started coming on showing a code of P0306 #6 cylinder misfire... Now my previous truck was a 2006 Scab 5.4 so I know about misfires. I am thinking coil packs again.... So I take it to my mechanic and ask him to change only the spark plug on cylinder 6 to see if its a plug, he changes it, clears the code and it comes back a day or two later. Now i take it back and ask that he change the coil pack on cylinder 6 hoping that it will be that. He changes it, clears the code and in a few days it comes back again, always P0306. I can diagnose the code and clear it myself but it keeps coming back... It is intermittent but always P0306. I switched coil packs and the misfire stayed on the #6 cylinder. Would a valve or injector problem be so intermittent? Any ideas????
Thanks In Advance!!!!

Docboz

Im having cyl 2&8 misfires on a brand new engine, replced coils, plugs and injectors, still misfiring. Going to wring out the harness with my multi meter today.

gDMJoe

Other possible causes ...

• faulty fuel injector
• burned exhaust valve

RLXXI

Check the injector connector/harness, could be rodent damage.