This has become a joke........I had a mis fire on #8, changed cap, roater, plugs, wires, still there, had CAT converter tested and checked, still there, did a compression test through the roof good, changed the crank sensor, still no luck, set and reset timing. I guess I will check the injector pressures now and the last will be the CPU for the vehicle its self..Basic maintenance has turned bad for me this year. So far, AC service, rear, and front seals, all gaskets as well, wires, plugs, cap and roater button, transmission service, valve adjustments, new tires, fuel pump, starter,and alternator..Im sure I missed a few things but that little skip, mis fire is really getting on my last nerve. Truck runs like a top and I do major maintenance every 70-85K with minor maintenance inbetween. I am almost at my witts end on this skip, what else could it be? other than the injector or the CPU. I did take the CPU off and put it on another truck like mine and the same misfire was there, Same? Maybe this is a good excuse to have my injectors cleaned properly. Any ideas let me know? Im sure I missed a few things the list is getting long..Thanks

 

It could very easily be a clogging injector. When Mopar went to single line fuel delivery systems, problems started developing with fuel injector clogging. When the fuel system had a return line to the tank, any crap that came up the line had a way back out. Now, it sits in the fuel rails. It usually migrates toward the rear of the rails. It usually shows up as a #7 or #8 misfire (the 2 rearmost injectors).

I saw that you had to replace the fuel pump recently. Sometimes degraded o-rings from the failing pump will send little nitrile rubber bits up the fuel line. These pieces are small, but wont make it through the injectors.