shadow7663
Expert Expediter
Having a tough time with this issue so heres the skinny. Last week truck starts running extremely poor on the low rpm side. runs great on the High rpm end.
Took the truck in had all new injectors installed, new pass throughs, new exhaust manifold (old one was cracked) new turbo installed (old one was cracked). After all that still the rough idle. 2 of the injectors were confirmed bad before replacing. After this we found a bad transient surpressor, replaced that, replaced the fuel pressor sensor. Still no change. So we put a test ecm on the truck, Truck runs great no issues, put old ecm back on truck runs horrible again. Ok so it must be the ECM mechanic says. So purchase a ecm today had it calibrated yada yada put it on and the truck still runs horrible.
Engine only runs bad once its warmed up. Oil levels good no coolant in oil no fuel in oil. Not smoking. No engine codes.
2 months ago installed brand new from Cummins fuel injection pump and lift pump. All parts installed on this truck have been genuine Cummins parts installed by Cummins.
I am at a loss here and need some help. Anyone have any suggestions?
Took the truck in had all new injectors installed, new pass throughs, new exhaust manifold (old one was cracked) new turbo installed (old one was cracked). After all that still the rough idle. 2 of the injectors were confirmed bad before replacing. After this we found a bad transient surpressor, replaced that, replaced the fuel pressor sensor. Still no change. So we put a test ecm on the truck, Truck runs great no issues, put old ecm back on truck runs horrible again. Ok so it must be the ECM mechanic says. So purchase a ecm today had it calibrated yada yada put it on and the truck still runs horrible.
Engine only runs bad once its warmed up. Oil levels good no coolant in oil no fuel in oil. Not smoking. No engine codes.
2 months ago installed brand new from Cummins fuel injection pump and lift pump. All parts installed on this truck have been genuine Cummins parts installed by Cummins.
I am at a loss here and need some help. Anyone have any suggestions?
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