Symptom Tree
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 for fault code troubleshooting. 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. Make sure the propeller size is correct. |
Engine is operating above recommended altitude (STC engines only) |
Derate the engine by 4 percent for every 300 meters [1000 feet] of altitude above 3600 meters [12,000 ft]. Refer to the Engine Data Sheet. |
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 or below specification |
Check the oil level. Add or drain oil, if necessary. 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 010-058 (Air Intake Piping) in Section 3. |
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 a Cummins Authorized Repair Location. |
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 or replace the fuel lines, check valves, or tank vents as needed. Refer to a Cummins Authorized Repair Location. |
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. |
Contact a Cummins Authorized Repair Facility |