Rawze.com: Rawze's ISX Technical Discussion and more

Baby Cummins, 2014 ISB. Replaced all injectors due to codes and almost unable to run. Cylinder cutout showed three bad. #1 and I think 3 and 4. Notes at work. Day later truck back,#1 injector bad. No codes but had a definite miss and making a lot of black grey smoke. Using Insite cut out injectors. When #1 cutout engine smoothed out and smoke quit. Swapped 1 with 3 to confirm injector and not cylinder. Problem followed injector. Replaced it and the UVC harness to the injectors. No codes, 20 mile road test, ran great. ASSumed (I Know) it was a bad injector. Returned to service. Back next day, same issue, #1 injector again. Again no codes. Suspect ECM at this point but would like to verify. Is there anything Insite can show me. Tomorrow I am going OHM injector then try using a noid light on the injector. Might even try a scope which I have never done. The fact that all three places I use for Cummins parts all have 1 or 2 ECM's in stock make mes think they might be a problem. One last thing. Any source other than Cummins for the ECM? A search Fri. and yesterday didn't show me much AND what is the quality. Thanks

i dont know if ISB are like the ISX did you put the information into the ECM with new injector code/part numbers? in the ISX models CM-2250-2350s the injectors have special numbers that need to be fed into the ECM so that it can run injectors correctly for fuel trim.

Ive had 1 or 2 injectors bad straight from cummins.

carbon packing at the intake valves of a cylinder can also cause repeating injector failures + weakened cylinder(s). Seen that on the ISX. Most people don't find it until they pull off the ECM cooling plate etc. because #1 and #2 are behind everything and you can't see the problem right away.

Will take a good look in the intake. ISB injectors don't need addressed or trimmed. Thanks for the input. Hate not being able to pinpoint cause of failure.

(06-02-2019 )DVT873 Wrote: [ -> ]Will take a good look in the intake. ISB injectors don't need addressed or trimmed. Thanks for the input. Hate not being able to pinpoint cause of failure.

fire it up,.. put an oscilloscope on the injectors. Look for negative spikes at edges of firing points. - Maybe ECM has a bad spike suppression diode for the coil?