M11 Industrial Operation and Maintenance – Engine Power Output Low

Electronic fault codes are active

For instructions on how to read active fault codes, refer to Procedure 101-007 (Electronic Controlled Fuel System) in Section 1. If fault codes are active, contact a Cummins Authorized Repair Facility.

Drivetrain is not correctly matched to the engine

Check for correct gearing and drivetrain components. Refer to the OEM service manual.

Engine is operating above recommended altitude

Engine power decreases above recommended altitude. Refer to the Engine Data Sheet for specifications.

Turbocharger is not correct

Check the turbocharger part number and compare it to the Control Parts List (CPL), Bulletin 3379133 or 4021327. Replace the turbocharger if necessary. Refer to Procedure 010-033 (Turbocharger) in Section A.

Fuel filter or fuel suction line is restricted

Replace the fuel filter. Refer to Procedure 006-015 (Fuel Filter – Spin-on) in Section 4. Check the fuel suction line for restriction Procedure 006-015 (Fuel Filter – Spin-on) in Section 4.

Lubricating oil level is above specification

Check the oil level. Verify the dipstick calibration and oil pan capacity. Fill the system to the specified level. Refer to Procedure 007-043 (Lubricating Oil Level) in Section 3.

Air intake system restriction is above specification

Check the air intake system for restriction. Clean or replace the air filter and inlet piping as necessary. Refer to Procedure 010-024 (Air Leaks, Air Intake and Exhaust Systems) in Section 5.

Air intake or exhaust leaks

Check for loose or damaged piping connections and missing pipe plugs. Check the turbocharger and exhaust manifold mounting. Refer to Procedure 010-024 (Air Leaks, Air Intake and Exhaust Systems) in Section 5.

Air in the fuel system

Check for air in the fuel system. Tighten or replace the fuel connections, fuel lines, fuel tank standpipe, and fuel filters as necessary.

Fuel drain line restriction

Check the fuel drain lines for restriction. Clear or replace the fuel lines, check valves, or tank vents as necessary.

Fuel grade is not correct for the application or the fuel quality is poor

Operate the engine from a tank of high-quality fuel. Refer to Procedure 018-002 (Fuel Recommendations and Specifications) in Section V.

Intake manifold air temperature is above specification

Refer to the Intake Manifold Air Temperature Above Specification symptom tree.

Fuel inlet temperature to pump is above specification

Fill the fuel tank, turn off or bypass the fuel heaters, and check the fuel cooler. Refer to the OEM service manual.