Cylinder 5 misfire. Tried everything I can think of!
#1
Cylinder 5 misfire. Tried everything I can think of!
took the truck to the dyno tuner noticed a cylinder 5 misfire. I swapped coil and injector on the dyno. Still had cylinder 5 misfire. Changed plug wire and plug. Still cylinder 5 misfire. Came home traced all the injector and coils back to the pcm everything was good. Did a compression test all the cylinders matched up. Today I pulled the head valves and lifters were fine. Cylinder walls look good. The way I have been testing it was on the hptuner scanner I turn off an individual injector and you can hear the engine make a noticeable change and runs rough. When I turn off cylinder 5 there's no change at all. I pulled the rail off the intake and verified the injector is firing...it is. Now idk what else to check.
#7
TECH Junkie
Im assuming you used known good parts from other cylinders when you switched and then switched back assuring they werent damaged in the process with no change. I've gotten bad new parts before. Go through it again to verify one more time...sucks.