GM Service Manual Online
For 1990-2009 cars only

Exhaust Manifold Replacement - Right Side 4.3L

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the exhaust pipe from the exhaust manifold. Refer to Exhaust Manifold Pipe Replacement .
  3. Lower the vehicle.

  4. Object Number: 172977  Size: SH
  5. Remove the bolt to the oil level indicator tube.
  6. Notice: Twist the spark plug boot one-half turn in order to release the boot. Pull on the spark plug boot only. Do not pull on the spark plug wire or the wire could be damaged.

  7. Remove the spark plug wires from the spark plugs.
  8. 5.1. Rotate the spark plug wire boot one half turn.
    5.2. Pull outward on the spark plug wire boot to release from the spark plug.
  9. Remove the spark plug wires from the spark plug wire retainers.

  10. Object Number: 341277  Size: SH
  11. Remove the nuts holding the secondary air injection (AIR) pipe assembly, if equipped to the exhaust manifold.
  12. Remove the AIR pipe and gasket from the exhaust manifold.

  13. Object Number: 188121  Size: SH
  14. Remove the exhaust manifold bolts.
  15. Remove the spark plug wire shields and the exhaust manifold.

  16. Object Number: 328555  Size: SH
  17. Remove and discard the exhaust manifold gaskets.
  18. Clean the exhaust manifold gasket mating surfaces. Refer to Exhaust Manifold Cleaning and Inspection in Engine Mechanical - 4.3 L Unit Repair.

Installation Procedure


    Object Number: 476818  Size: SH

    Important: To assist in installing the exhaust manifold to the engine, the tabs at the bolt holes on a NEW exhaust manifold gasket will hold the bolts and the gaskets in place.

  1. Install the exhaust manifold gaskets to the exhaust manifold.

  2. Object Number: 188121  Size: SH
  3. Install the exhaust manifold.
  4. Install the spark plug wire shields.
  5. Apply threadlock GM P/N 12345493 or equivalent to the threads of the exhaust manifold bolts.
  6. 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.

  7. Install the exhaust manifold bolts.
  8. Tighten

    1. Tighten the exhaust manifold bolts on the first pass to 15 N·m (11 lb ft).
    2. Tighten the exhaust manifold bolts on the final pass to 30 N·m (22 lb ft).
  9. Install the spark plug wires to the spark plug wire retainers.
  10. Install the spark plug wires onto the spark plugs.

  11. Object Number: 341277  Size: SH
  12. Install a new AIR pipe gasket and the AIR pipe to the exhaust manifold.
  13. Install the AIR pipe nuts.
  14. Tighten
    Tighten the AIR pipe nuts to 25 N·m (18 lb ft).

  15. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  16. Install the exhaust pipe to the exhaust manifold. Refer to Exhaust Manifold Pipe Replacement .
  17. Lower the vehicle.

  18. Object Number: 172977  Size: SH
  19. Install the bolt for the oil level indicator tube.
  20. Tighten
    Tighten the oil level indicator tube bolt to 12 N·m (106 lb in).