B5.9G, B5.9LPG, B Gas Plus, B LPG Plus – Intake Manifold Pressure (Boost) is Below Normal

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. If fault codes are active, contact a Cummins Authorized Repair Facility.


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 010-058 (Air Intake Piping) in Section 3 or a Cummins Authorized Repair Facility.


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 010-059 (Air Cleaner Restriction) in Section 4 and Procedure 010-027 (Charge-Air Cooler) in Section A.


Charge air cooler is restricted or leaking

Inspect the charge air cooler for air restrictions or leaks. Refer to Procedure 010-027 (Charge-Air Cooler) in Section 5.


Engine power output is low

Refer to the Engine Power Output Low symptom tree.


Engine is operating above recommended altitude

Engine power decreases above recommended altitude. Refer to the engine data sheet for specifications.

Contact a Cummins Authorized Repair Facility

Last Modified:  16-Feb-2005