GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2005 🢒 Terraza 🢒 Preface 🢒 Cautions and Notices 🢒 Exhaust Manifold Replacement - Right Side

Removal Procedure
  1. Remove the throttle body air inlet duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls - 3.5L.

    2. Object Number: 621066 Size: SH
  2. Disconnect the exhaust gas recirculation (EGR) pipe at the EGR valve.
  3. Unscrew the EGR pipe assembly nut from the exhaust manifold and remove the pipe from the vehicle.

    4. Object Number: 187050 Size: SH
  4. Remove the exhaust manifold heat shield bolts.
  5. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle .
  6. Remove the exhaust manifold heat shields.
  7. Remove the EGR pipe from the exhaust manifold and remove from the vehicle.

    8. Object Number: 187052 Size: SH
  8. Remove the exhaust manifold nuts.
  9. Remove the exhaust manifold.
  10. Remove the exhaust manifold gasket.
  11. Clean the engine right side exhaust manifold sealing surfaces and the cylinder head sealing surfaces.

Installation Procedure
  1. If removed, install the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor 1 Replacement in Engine Controls - 3.5L.

    2. Object Number: 187052 Size: SH
  2. Install the exhaust manifold gasket.
  3. Install the exhaust manifold.

    4. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the exhaust manifold nuts.

    5. Tighten
    Tighten the exhaust manifold nuts to 16 N·m (12 lb ft).


    Object Number: 187050 Size: SH
  5. Install the exhaust manifold lower heat shield.
  6. Install the exhaust manifold upper heat shield.
  7. Install the exhaust manifold heat shield bolts.

    8. Tighten
    Tighten the exhaust manifold heat shield bolts to 10 N·m (89 lb in).


    Object Number: 621066 Size: SH
  8. Install the EGR valve pipe to the exhaust manifold.

    9. Tighten
    Tighten the EGR pipe nut to 25 N·m (18 lb ft).

  9. Install the catalytic converter. Refer to Catalytic Converter Replacement .
  10. Connect the HO2S electrical connector.
  11. Lower the vehicle.
  12. Install the exhaust crossover pipe nuts/studs to the engine right side exhaust manifold. Refer to Exhaust Crossover Pipe Replacement .
  13. Install the EGR pipe bolt to the EGR valve.

    14. Tighten
    Tighten the EGR pipe bolt to 25 N·m (18 lb ft).

  14. Install the throttle body air inlet duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls - 3.5L.