GM Service Manual Online
For 1990-2009 cars only
    • Review the Exhaust System Description and Operation in order to familiarize yourself with the system functions. Refer to Exhaust System Description .
    • All diagnostics on a vehicle should follow a logical process. Strategy Based Diagnostics is a uniform approach for repairing all systems. The diagnostic flow is the place to start when repairs are necessary and may always be used in order to resolve a system problem.

Visual/Physical Inspection

    • Inspect for aftermarket or non-OEM devices such as, but not including; tailpipe extensions, headers, and exhaust cutouts. This could affect the operation and proper performance of the exhaust system.
    • Verify the exact operating conditions under which the concern exists. Note factors such as engine RPM, engine temperature, engine load, and frequency of concern.
    • Inspect the easily accessible or visible system components for obvious damage or conditions, which could cause any symptom.

Intermittents

Test the vehicle under the same conditions that the customer reported in order to verify the system is operating as designed.

Symptom List

    • Loss of power--Refer to Restricted Exhaust .
    • Poor acceleration--Refer to Restricted Exhaust .
    • Poor fuel economy--Refer to Restricted Exhaust .
    • Excessive smoke-diesel--Refer to Restricted Exhaust .
    • Exhaust hissing noise--Refer to Exhaust Leakage .
    • Exhaust popping noise--Refer to Exhaust Leakage .
    • Exhaust rattle noise--Refer to Exhaust Noise .
    • Loud Exhaust noise--Refer to Exhaust Noise .
    • Exhaust buzz, groan, hum noise--Refer to Exhaust Noise .