So in that case if its white smoke doesnt mean injector is problem.Nozzles are but one area. Bodies don't wear out, the ball seat and solenoid ball is what wears out on high milage units. Only a bosch dealer with the required calibration equipment can purchase the required parts to rebuild them completely. Many have bought the diy nozzle kits, and almost all of them end up smoking afterwards.
As to smoke colir, injectors CAN smoke blue. I have actually yet to have an lb7 come to me white smoking needing injectors. I've had one grey smoking, but the majority have been blue smoke. Just did mine for blue smoke. Doing the GM cleaner cleared up most of the blue smoke, but it would randomnly blow out a plume of blue after flushing. Remember, diesel is fuel OIL, and burns by compression same as oil will. Dribbling nozzles can easily cause blue smoke from fuel entering before cylinder heat is high enough, but not enough fuel entering to put the fire out(thats what causes white smoke).
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