GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    CAUTION:: Always wear protective goggles and gloves when removing exhaust system parts as falling rust and sharp edges from worn exhaust components could result in serious personal injury.

    When removing exhaust components, the accumulation of dirt and corrosion can make work difficult. Using a penetrating oil on the threads can assist in the removal of these components.


    Object Number: 42809  Size: SH

    Object Number: 42809  Size: SH
  1. Disconnect the negative battery cable. Refer to

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

    in General Information.
  2. Drain the air lines. Close the drain valves when all pressure is released.
  3. Disconnect the air lines attached to the control assembly.
  4. Remove the screws, the washers and the control assembly from the mounting plate.

Installation Procedure


    Object Number: 42809  Size: SH
  1. Mount the control assembly in place using the screws and the washers.
  2. Attach the air lines to the control assembly.
  3. Connect the negative battery cable.
  4. Start the engine. Allow the air system to pressurize.
  5. Check the air connections for leaks.