2004.5 - 2005 GM 6.6L LLY Duramax CP3 Pump Regulator
The CP3 pump regulator controls the fuel pressure that is being sent to the injector fuel rails and the injectors themselves. Over time these will wear out or be contaminated causing inaccurate pressure control. It is common to have an uneven idle or a loping idle. If the problem is bad enough the varying idle RPM can cause the vehicle to want to move while stopped.
Typical life expectancy of the CP3 pump is 150,000 miles. If your pump is near or past this mileage our recommendation is to not replace just the regulator, but instead install a whole new pump that comes with a new regulator installed.
Old number = Bosch 0928400653
Find all your GM LLY Duramax diesel performance, repair, and upgrade needs here online or in person at Huckstorf Diesel’s sales and repair center located in Franklin / Milwaukee Wisconsin.
