GM Service Manual Online
For 1990-2009 cars only

Caution: Engine exhaust contains Carbon Monoxide (CO) which cannot be seen or smelled. Exposure to CO can cause unconsciousness and even death.

Exhaust may enter the vehicle if:

   • The vehicle idles in areas with poor ventilation (parking garages, tunnels, deep snow that may block underbody airflow or tail pipes).
   • The exhaust smells or sounds strange or different.
   • The exhaust system leaks due to corrosion or damage.
   • The vehicle’s exhaust system has been modified, damaged or improperly repaired.
   • There are holes or openings in the vehicle body from damage or after-market modifications that are not completely sealed.
If unusual fumes are detected or if it is suspected that exhaust is coming into the vehicle:
   • Drive it only with the windows completely down.
   • Have the vehicle repaired immediately.
Never park the vehicle with the engine running in an enclosed area such as a garage or a building that has no fresh air ventilation.

Caution: While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system.

Notice: If there is any mis-positioning, incorrect installation, or failure of components in the brake system pipes, hoses, or wheel cylinders, check for brake damage. The exhaust system components must have adequate clearance from the floor pan to avoid overheating of the floor pan, damage to the passenger compartment carpets and damage to items in the luggage compartments.

Muffler

Important: Use of non-OEM parts may cause driveability concerns.

The exhaust system carries exhaust gases, treated by the catalytic converter, through a resonator, if applicable and into the exhaust muffler where exhaust noise is lessened.

In order to secure the exhaust pipe to the exhaust manifold, a flange and seal joint coupling is utilized. The exhaust system may utilize a slip-joint coupling design with a clamp and a U-bolt or a flange connection with a gasket.

Exhaust hangers and rubber insulators help to support the weight of the exhaust pipe along with insulating any exhaust system vibration, rattle, or noise.

Exhaust hangers also space the exhaust system away from the underbody of the vehicle and allows the exhaust system to expand as the exhaust system warms up.

Exhaust heat shields are used to protect the body and other components from damage due to the heat from the exhaust system.

The exhaust system may be comprised of the following components:

    • Exhaust manifold
    • Exhaust pipes
    • Catalytic converters
    • Exhaust muffler
    • Exhaust resonator, if equipped
    • Exhaust tail pipe, if equipped
    • Exhaust hangers
    • Exhaust heat shields

If holes, open seams or any deterioration is discovered upon inspection of the front muffler and pipe assembly, the complete assembly should be replaced. The same procedure is applicable to the rear muffler assembly.

Catalytic Converters

Notice: The catalytic converters require the use of unleaded fuel only. Using leaded fuel will damage the catalytic converters and other emission system components.

The catalytic converters are emission control devices added to the exhaust system to reduce pollutants from the exhaust pipes.

The 3-way catalyst has coatings which contain palladium, platinum and rhodium, which simultaneously lower the levels of HC, CO and NOx.