Cummins ISX CM870 (2003-06) Fault Code: 2552 PID: P157 SPN: 157 FMI: 0/16 Front Fueling Actuator Pressure High – Warning. Unexpected high fueling detected on the front bank.

The ECM estimates the amount of fuel injected into the front and rear banks of the engine by analyzing the acceleration of the crankshaft. This fault is set active when the estimate of fueling on the front bank is higher than expected.

Possible repairs:

1)Replace the rear fueling actuator (return the front actuator to its original position).
2)Return the front and rear fueling actuators to their original positions.
3)Replace the rear timing actuator.