Cummins ISX11.9 CM2250 – Service Manual Intake Manifold Pressure (Boost) is Below Normal

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.

Intake manifold pressure sensor is malfunctioning

Check the intake manifold pressure sensor. Refer to
Procedure 019-159 in Section 19
.

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 in Section 10
.

Charge-air cooler is restricted or leaking

Inspect the charge-air cooler for air restrictions or leaks. Refer to
Procedure 010-027 in Section 10
.

Air intake system restriction is above specification

Check the air intake system for restrictions. Clean or replace the air filter and inlet piping as necessary. Refer to
Procedure 010-031 in Section 10
.

Turbocharger is worn or damaged

Check the turbocharger for damage. Measure the turbine and compressor wheel clearances. Refer to
Procedure 010-033 in Section 10
.

Air compressor connection is loose or damaged

Check the connection between the manifold and the air compressor. Repair or replace if necessary.

Turbocharger is not correct

Check the turbocharger part number and compare it to the Control Parts List (CPL), Bulletin 4021328. Replace the turbocharger if necessary. Refer to
Procedure 010-033 in Section 10
.

Exhaust system restriction

Check the exhaust system for restrictions. Refer to
Procedure 011-009 in Section 11
.

Engine power output is low

Refer to the Engine Performance Troubleshooting Tree in Section TT.