Cummins ISX11.9 CM2250 – Service Manual Engine Decelerates Slowly

Electronic fault codes active or high counts of inactive fault codes

Refer to Section TF in the Fault Code Troubleshooting Manual, Bulletin
4022225, for fault code troubleshooting.

Accelerator pedal or lever is restricted or malfunctioning

Check the percent accelerator pedal or lever reading on an electronic service tool. Verify that it reads 100 percent with the accelerator pedal depressed and 0 percent when released. Calibrate the accelerator if possible. Replace the accelerator pedal, if necessary. Refer to the OEM service manual.

Air in the fuel system

Check for air in the fuel system. Refer to
Procedure 006-003 in Section 6
.

Injector o-rings are damaged or missing

Remove and check the injectors. Replace the injector o-rings. Refer to
Procedure 006-026 in Section 6
..

Injector is malfunctioning

Perform the automated cylinder performance test. Replace injectors as necessary. Refer to Procedure 006-026 in Section 6 or
Procedure 014-008 in Section 14.

Turbocharger oil seal is leaking

Check the turbocharger compressor and turbine seals. Refer to
Procedure 010-033 in Section 10
.