Lack Of Lift Pump
All Duramax engine types lack one important element to their fuel system, and that's a fuel lift pump. This is a very important part for maintaining proper fuel system lubrication and longevity. This also creates a road block in the Duramax performance when equipped with chips or tuners. Without a factory equipped lift pump, the Duramax relies completely on the CP3 high-pressure injection pump to do all the work of pulling the fuel from the fuel tank to the injection system. When the CP3 is put under this kind of stress it's easy to run out of fuel to the injection system and starve the injectors and injection pump of the precious fuel they require to lubricate the system. This will drastically reduce the life of your injectors and injection pump. Not to mention with a lack of fuel comes a lack of performance, so naturally upgrading to an aftermarket lift pump or fuel delivery system is a no-brainer.