cummins isx15 injector

[Ibanes]

if i need to replace injectors on a cummins isx15 do i have to do it in some kind of order or timing? i know i need to write down #s and program through insite.. this truck had a bad fuel pump,(replaced) cam shaft had damaged (replaced) turbo and actuator (replaced) injector harness (replaced) throttle actuator (replaced) egr tune up performed..exhaust manifold (replaced) i also took the complete dpf system out of a good running sister truck that was crashed in front.. truck has the following codes # 3545, #1144 active and inactive are codes #3253, #3311 i tried to run re-gen and it fails.. performed the injector test and #5 fails..any ideas? sorry for question i am at my last nerve with this truck..[/b]