CM2350 derate 6255 only no fault codes

[Rawze]

(09-22-2023 )greg1227 Wrote:  Thanks for the response
It is not de mandated all factory . We had replaced exhaust sensor recently ( month or so ) with a Cummins sensor . We have the latest ECM update from a friend with a factory Cummins computer . We did see oil in the valve cover connector so that will be something we will deal with . Did not do rail test will do that as well . We ohmd the wiring from ecm to connector at valve cover all exactly the same and wiggled wires during test . Will address all of your concerns on Monday when i get back to shop . Still wondering why it would show a single count for the misfire fault and then show derate in 30 minutes . Now no code except derate code and instantly when doin a injector performance test . Will do all testing Monday and get back thanks again

Push comes to shove, if no one can solve it, someone might have to record the 'CBL_Fuel_State', engine mode control, and other settings in the ecm using the Clalterm software and some desktop recording software. Get it to act up under normal load conditions instead of that mostly useless injector performance test crap. This will at least reveal what manager or system in the ecm is controlling the derate condition.