N14 Base Engine Troubleshooting and Repair Manual – Engine Power Output Low (CELECT™ or CELECT™ Plus)

Electronic fault codes active or high counts of inactive fault codes

Refer to Section TF in the Troubleshooting and Repair Manual, CELECT™ Plus Systems, Bulletin 3666130, or Section TF in the Troubleshooting and Repair Manaul, CELECT™ Systems, Bulletin 3666084.

Interview the operator to verify the complaint

Refer to Driveability – General Information, the Driveability/Low Power Customer Complaint Form, and the Driveability Checklist at the end of Section TS. Follow the instructions on the form before continuing with this tree.

Electronic control module (ECM) calibration is malfunctioning

Verify the ECM calibration is correct. Check the calibration revision history for applicable fixes to the calibration stored in the ECM. Refer to the calibration history spreadsheet Click here to see ecm_calibration_rev_history.xls

on QuickServe® Online or the INCAL™ CD-ROM. Compare the calibration stored in the ECM with the engine rating and the Control Parts List (CPL), Bulletin 4021326 or 4021327. If necessary, recalibrate the ECM. Refer to Procedure 019-032 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Programmable parameters or selected features are not correct

Check the programmable parameters and the selected features with an electronic service tool. Set the parameters and features again if necessary. Refer to the appropriate electronic service tool manual and Procedure 019-078 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Drivetrain is not correctly matched to the engine

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

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 Procedures 007-009 and 007-037.

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

Operate the engine from a tank of good fuel. Refer to Fuels for Cummins Engines, Bulletin 3379001.

Air intake or exhaust leaks

Inspect the air intake and exhaust systems for air leaks. Refer to Procedure 010-024.

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.

Air intake system restriction

Check the air intake system for restriction. Refer to Procedure 010-031.

Intake manifold air temperature is above specification

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

Charge air cooler is restricted or leaking

Inspect the charge air cooler for air restrictions or leaks. Refer to Procedure 010-027.

Intake manifold pressure (boost) is below specification

Refer to the Intake Manifold Pressure (Boost) is Below Normal symptom tree.

Throttle position sensor or circuit malfunctioning (if equipped with a throttle position sensor)

Check the throttle position sensor and circuit. Refer to the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Tachometer or speedometer is not calibrated or is malfunctioning

Compare the vehicle tachometer and speedometer readings with an electronic service tool reading. Check the calibration values for the flywheel teeth, rear axle ratio, and tire revolutions. Adjust the values if necessary. Refer to the OEM service manual.

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.

Engine protection fault code(s) inactive

Refer to Section TF in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or Section TF in the Troubleshooting and Repair Manaul for CELECT™ Systems, Bulletin 3666084. View the fault codes and the engine protection data with an electronic service tool. Refer to the appropriate electronic service tool manual.

Vehicle speed sensor (VSS) or circuit is malfunctioning

Use an electronic service tool to monitor the vehicle speed while the vehicle is not moving. Refer to the appropriate electronic service tool manual. If the monitor shows speed, check the sensor and circuit. Refer to Procedure 019-090 or 019-091 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Intake manifold temperature sensor is malfunctioning

Check the intake manifold temperature sensor. Refer to Procedures 019-059 and 019-060 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Coolant temperature sensor is malfunctioning

Check the coolant temperature sensor. Refer to the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Ambient air pressure sensor is malfunctioning (if equipped)

Check the ambient air pressure sensor. Refer to Procedure 019-134 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Intake manifold pressure (boost) sensor or circuit is malfunctioning

Check the boost sensor and circuit. Refer to Procedure 019-061 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Governor setting is not correct in the programmable parameters

Verify if the driver is accustomed to the automotive governor or the VS governor. Change the governor setting if necessary. Refer to the appropriate electronic service tool manual.

Fuel supply pressure is below specification

Measure the fuel supply pressure. Refer to the OEM service manual.

Fuel supply line restriction between the fuel pump and the injectors

Check the fuel supply line from the fuel pump to the cylinder head for sharp bends that can cause restrictions. Refer to the OEM service manual.

Turbocharger wheel clearance is out of specification

Check the radial bearing clearance and axial clearance. Inspect the turbocharger. Repair or replace the turbocharger if necessary. Refer to Procedures 010-038 and 010-047.

Engine components are not correct

Compare the Control Parts List (CPL) to the engine components. Replace components that do not meet CPL requirements. Refer to the Control Parts List, Bulletin 3379133.

Overhead adjustments are not correct

Check and adjust the overhead settings. Refer to Procedure 003-004.

Crankcase pressure is excessive

Check for excessive blowby. Refer to the Crankcase Gases (Blowby) Excessive symptom tree.

Engine is operating at high ambient temperature

Use outside air to the turbocharger in hot weather.

Engine is operating at low ambient temperature

Check the winterfront, shutters, and under-the-hood air. Use under-the-hood intake air in cold weather. Refer to Operation of Diesel Engines in Cold Climates, Bulletin 3379009.

Fuel temperature is above specification

Fill the fuel tanks. Turn off or bypass the fuel heater, if equipped. Refer to the OEM service manual.

Fuel drillings in the cylinder head are plugged

Check for a plastic fuel passage plug blocking the fuel supply to the injectors. Refer to Procedure 002-004.

Keyswitch circuit is malfunctioning

Check the vehicle, equipment, or vessel keyswitch circuit. Refer to Procedure 019-064 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or the Troubleshooting and Repair Manual for CELECT™ Systems, Bulletin 3666084.

Air in the fuel system

Check for air in the fuel system. Completely vent air from the fuel system. Refer to Procedure 006-003.