GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2003 🢒 Montana 🢒 Engine 🢒 Engine Exhaust 🢒 Exhaust Manifold Replacement - Right Side

Removal Procedure
  1. Remove the windshield wiper motor cover. Refer to Wiper Module Cover Replacement in Wipers/Washer Systems.
  2. Remove the throttle body air inlet duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls - 3.4L.
  3. Remove the accelerator cable bracket from the throttle body. Refer to Accelerator Control Cable Replacement in Engine Controls - 3.4L.
  4. Rotate the engine for service access. Refer to Rotating the Engine for Service Access .
  5. Remove the manifold air pressure (MAP) sensor. Refer to Manifold Absolute Pressure Sensor Replacement in Engine Controls - 3.4L.
  6. Remove the exhaust gas recirculation (EGR) valve. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 3.4L.
  7. Remove the ignition module and the ignition coils with the bracket.
  8. Remove the spark plug wires from the engine right bank spark plugs.
  9. Disconnect the oxygen sensor electrical connector.
  10. Remove the evaporative emissions (EVAP) solenoid bracket.
  11. Remove the exhaust crossover pipe nuts/studs from the engine right bank exhaust manifold. Refer to Exhaust Crossover Pipe Replacement .
  12. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  13. Remove the catalytic converter. Refer to Catalytic Converter Replacement .

    14. Object Number: 187050 Size: SH
  14. Remove the exhaust manifold heat shield bolts.
  15. Remove the exhaust manifold heat shields.

    16. Object Number: 187052 Size: SH
  16. Remove the exhaust manifold nuts.
  17. Remove the exhaust manifold.
  18. Remove the exhaust manifold gasket.
  19. Lower the vehicle.
  20. Clean the engine right side exhaust manifold sealing surfaces and the cylinder head sealing surfaces.
  21. If you are REPLACING the engine right side exhaust manifold, remove the Exhaust Gas Recirculation (EGR) valve pipe.
  22. If you are REPLACING the engine right side exhaust manifold, remove the Heated Oxygen Sensor (HO2S). Refer to Heated Oxygen Sensor 1 Replacement in Engine Controls - 3.4L.

Installation Procedure
  1. If removed, install the Heated Oxygen Sensor (HO2S). Refer to Heated Oxygen Sensor 1 Replacement in Engine Controls - 3.4L.
  2. If removed, install the exhaust gas recirculation (EGR) valve pipe.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

    4. Object Number: 187052 Size: SH
  4. Install the exhaust manifold gasket.
  5. Install the exhaust manifold.

    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.

  6. Install the exhaust manifold nuts.

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


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

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

  10. Install the catalytic converter. Refer to Catalytic Converter Replacement .
  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 exhaust crossover pipe heat shield. Refer to Exhaust Crossover Pipe Replacement .
  14. Lower the vehicle.
  15. Connect the Heated Oxygen Sensor (HO2S) electrical connector.
  16. Install the EVAP solenoid bracket.
  17. Install the spark plug wires to the engine right bank spark plugs.
  18. Install the ignition module and the ignition coils with the bracket.
  19. Install the EGR valve to the intake manifold. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 3.4L.
  20. Install the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement Engine Controls - 3.4L.
  21. Rotate the engine back to the original position. Refer to Rotating the Engine for Service Access .
  22. Install the accelerator cable bracket to the throttle body. Refer to Accelerator Control Cable Replacement in Engine Controls - 3.4L.
  23. Install the throttle body air inlet duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls - 3.4L.
  24. Install the windshield wiper motor cover. Refer to Wiper Module Cover Replacement in Wipers/Washer Systems.