George Schreffler
Newbie
No offense taken at any questions or suggestions because I am clearly missing something…and I hope it’s obvious and easy.
I agree that number 5 does not look like it’s firing.
Truck definitely runs like it has a misfire. Rough idle and rough running throughout operating range when cold. Idle gets smoother as the engine warms, but not like it should be. Rev it when warm or take in on the road and the misfire is immediately discernible.
The misfire counter on the scan tool backs up the seat-of-the-pants feel by logging misfires on cylinder 5, and cylinder 5 only, throughout the engine’s operating range. Interestingly, the DTC for a misfire specific to cylinder 5 does not set. I only get the P0300 DTC.
The misfire was present from the first start up with with new engine. It was also present in the old engine. The crack in cylinder 5 on the old engine led me to believe that was my problem. Clearly, the crack was not my only problem. Maybe it wasn’t even contributing to the misfire.
There are no visually observable mechanical issues with the valve train when cranking the new engine. Copy on resetting valve lash.
Visual inspections of the intake runner and fuel injector hole before assembly and installation indicate no debris or obstructions of any type.
No coolant or carbon build up in the exhaust runner. The cylinder heads are new, too, and were inspected before installing the intake manifold.
I agree that number 5 does not look like it’s firing.
Truck definitely runs like it has a misfire. Rough idle and rough running throughout operating range when cold. Idle gets smoother as the engine warms, but not like it should be. Rev it when warm or take in on the road and the misfire is immediately discernible.
The misfire counter on the scan tool backs up the seat-of-the-pants feel by logging misfires on cylinder 5, and cylinder 5 only, throughout the engine’s operating range. Interestingly, the DTC for a misfire specific to cylinder 5 does not set. I only get the P0300 DTC.
The misfire was present from the first start up with with new engine. It was also present in the old engine. The crack in cylinder 5 on the old engine led me to believe that was my problem. Clearly, the crack was not my only problem. Maybe it wasn’t even contributing to the misfire.
There are no visually observable mechanical issues with the valve train when cranking the new engine. Copy on resetting valve lash.
Visual inspections of the intake runner and fuel injector hole before assembly and installation indicate no debris or obstructions of any type.
No coolant or carbon build up in the exhaust runner. The cylinder heads are new, too, and were inspected before installing the intake manifold.