How do I know if my cp3 is bad?

Crank the engine over until fuel begins to flow from the hose from the CP3 return. Empty the container out, then crank it over for 15 seconds. Measure the amount of fuel in the container. If it is more than 1.2 onces, the CP3 is returning to much fuel and is bad.Click to see full answer. Keeping this in view, what is a cp3?High-pressure common-rail injection technology has revolutionized the diesel industry. The CP3 injection pump’s sole job is to create and regulate high-pressure fuel (it’s not timed with the engine’s crankshaft and camshaft).Beside above, what is a cp3 on a Cummins? This pump features 3 plungers, it is of variable displacement. All CP3’s from the light-duty engines, such as 5.9 and 6.7 as well as the Duramax engines, have the same bore and stroke for the plungers. There are none that are any larger unless they are modified to increase the displacement. how does the cp3 pump work? In order to meter the fuel into the chambers, the CP3 has an internal metering/lift pump built right into it. This pump takes the fuel at supply pressure and boosts it to pressures between 80 and 180 PSI depending on what is required.Where is the cp3 pump located on a Duramax?The pump is located in the engine valley (between the heads, at the front). Don’t worry about it or mess with it, just yet. If you have stalling or no start issues, it’s probably air in the system. Try pumping the primer (pump on the filter housing) until it is very hard to pump.