The 6.7-liter Cummins is known for having some fuel system issues that can involve the injectors, lift pump, fuel control actuator, and more. +Read more
Sometimes, the Bosch CP3 high-pressure injection pump can provide insufficient rail pressure, resulting in hard starts. At start-up, the rail pressure should be at least 4,000 psi; anything lower can indicate bad 6.7 Cummins injectors. The injectors should be replaced at regular maintenance intervals to ensure optimum performance.
A failing fuel control actuator can cause hard starts or no-start situations, a rough idle, and RPM surges. When the FCA is faulty, the engine control module is unable to determine the correct fuel flow rate to the 6.7 Cummins injection pump, making it so that the pump cannot build pressure.
ProSource Diesel offers a wide range of replacement parts for your Cummins turbo-diesel, including fuel injectors, 6.7 Cummins fuel lines, and more.