Detroit DD13 EPA07 (2007-09) Fault Code: SPN 1077 FMI 7 (MCM) Rail Pressure Deviation is Greater the 200 Bar for Eight Seconds

NOTE: The motor control module (MCM) sets the code.

POSSIBLE CAUSES:
1. External fuel leakage between the high pressure pump and fuel injectors.
2. Pressure limiting valve (PLV) leakage (Internal).
3. Fuel filter integrity (Loose caps, plugged filters).
4. Fuel supply issues (fuel level, fuel aeration, leaking fuel lines, fuel restrictions).
5. Intermittent loss of engine speed signal.
6. High pressure pump internal failure.
7. Fuel injector (amplifier or needle) leakage.
8. Fuel contamination.
9. Rail pressure sensor.
10. MCM.

PROBABLE CAUSES:
1. External fuel leakage between the high pressure pump and fuel injectors.
2. Pressure limiting valve leakage (internal).
3. Fuel filter integrity.
4. Fuel supply issue.
5. Intermittent loss of engine speed signal.
6. High pressure pump internal failure.
7. Fuel injector leakage.
8. Fuel contamination.
9. Rail pressure sensor.
10. Motor Control Module.