GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Allow the engine to cool before servicing the secondary air injection AIR system in order to reduce the chance of severe burns.

  1. Remove the check valve hose clamp.

  2. Object Number: 178463  Size: SH
  3. Disconnect the AIR hose from the check valve.
  4. Unscrew the check valve from the AIR pipe.
  5. Remove the left AIR pipe from the manifold.
  6. Before replacing a check valve, test the valve for proper operation.
  7. 5.1. Install a vacuum pump to the nipple side of the check valve, on the AIR pump side.
    5.2. Pump the vacuum pump to 10 inches Hg, and observe the gage.
    5.3. If the vacuum bleeds down to zero within 5 seconds, replace the check valve.

Installation Procedure


    Object Number: 178463  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Screw the check valve onto the AIR pipe.
  2. Tighten
    Tighten the check valve to the AIR pipe to 23 N·m (17 lb ft).

  3. Connect the AIR pipe to the exhaust manifold.
  4. Tighten
    Tighten the AIR pipe to the exhaust manifold to 20 N·m (15 lb ft).

  5. Install the AIR hose to the check valve.
  6. Install the check valve hose clamp.
  7. Check the AIR system for proper operation.