GM Service Manual Online
For 1990-2009 cars only
    • Review the exhaust system description in order to familiarize yourself with the exhaust system components and the intended function of the components. 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. For a detailed explanation, refer to Strategy Based Diagnosis.

Visual/Physical Inspection

    • Inspect for aftermarket or non-OEM devices such as, but not limited to; tailpipe extensions, headers, and exhaust cutouts. Any aftermarket exhaust system devices 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.

Intermittent

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

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

    • 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, humm noise
        Refer to Exhaust Noise