Misfire!? Need Help!
My buddy has a 2005 Gt that has a misfire and runs like ****, we cant figure it out, and theres no dealer warranty for it. So far we have changed everything from new plugs, coil packs, and injectors. I have no idea what else could be wrong with it, right now I'm thinking maybe his ECU is messed up and needs to be re-flashed or replaced by Ford. He bought it used and its been doing it from day one apparently. I think it has a stock tune on it, but idk if the previous owner possibly tuned it or not.
Here are the codes its throwing.
P0201 - CYLINDER 1 INJECTOR CIRCUT OPEN
PO305 - CYLINDER 5 MISFIRE
P0306 - CYLINDER 6 MISFIRE
PO316 - MISFIRE DETECTED ON STARTUP (FIRST 1000 REVOLUTIONS)
PO351 - IGNITION COIL A PRIMARY, SECONDARY CIRCUT
P0352 - IGNITION COIL B
PO353- IGNITION COIL C
Thanks for any help guys.