Truck Repair: n14 miss, n14 cummins, piston rings

Question
i have a 1999 n14 cummins that has a miss between shifts, at slow acceleration. replace the injector i think is bad runs good for a few months and starts again. i have replaced all six in two years,also the speed sensor behind the air pump.can the wiring be my problem shorting out the injectors. and when i say missing i mean smoking blue and never a code till the injector is out completely thanks   steve

Answer
Celect plus engines are better diagnosed through identification of specific faults code and interpret such using Cummins intelect sftware or any other compatible electronic diagnostic tools.

Since you indicated that you did not have any code, then you need to short out the injectors one after the other to determine the ones at fault. You can also rely on the exhaust temperature of each cylinder to determine which one is not firing well.

The blue smoke emission may point to a dire need to do engine overhaul i.e. piston rings and liner replacement to improve power.

Regards,