Detroit DD13 GHG14 (2014-16) Fault Code: SPN 1077 FMI 14 (MCM) Internal or External Leakage of the High Pressure Fuel System (Too High, Leak Down Test)

NOTE: The motor control module (MCM) monitors rail pressure during engine shut down and compares it to a stored learned value. If the bleed-down rate has changed due to leakage and it is below the learned value, this code will set.

DESCRIPTION:
Leakage in high pressure fuel system to high (leak down test).

MONITORED PARAMETER:
Fuel rail pressure.

TYPICAL ENABLING CONDITIONS:
Key off

MONITOR SEQUENCE:
None

EXECUTION FREQUENCY:
Once when enabling conditions met.

TYPICAL DURATION:
30 seconds

DASH LAMPS:
1. MIL
2. CEL

VERIFICATION:
FSIC Leak Test (GHG14)

PROBABLE CAUSES:
1. If any other codes present, fix those first.
2. Clear code and road test. If it doesn’t come back, return vehicle to customer.
3. Check for internal and external high pressure fuel system leakage.
4. Fuel injector failure.
5. Check for leakage from the pressure limiting valve.
6. High pressure fuel pump failure.