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For 1990-2009 cars only

Exhaust Manifold Replacement - Right Side 3.8L

Removal Procedure


    Object Number: 153575  Size: SH
  1. Remove the cross vehicle brace. Refer to Cross Vehicle Brace Replacement in Body Front End.
  2. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
  3. Remove the exhaust crossover heat shield nuts.
  4. Remove the exhaust crossover heat shield.

  5. Object Number: 153576  Size: MH
  6. Remove the exhaust crossover pipe bolts from the right exhaust manifold.
  7. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

  8. Object Number: 372626  Size: SH
  9. Remove the exhaust manifold pipe stud nuts and the catalytic converter pipe from the right exhaust manifold.

  10. Object Number: 154806  Size: SH
  11. Remove the exhaust gas recirculation (EGR) valve inlet adapter pipe bolt from the right exhaust manifold.
  12. Lower the vehicle.
  13. Rotate the engine to access the right side of the engine. Refer to Rotating the Engine for Service Access in Engine Mechanical - 3.8L.

  14. Object Number: 371512  Size: SH
  15. Disconnect the heated oxygen (HO2S) sensor electrical connector (4).
  16. Remove the heated oxygen (HO2S) sensor electrical connector (4) from the engine sight shield bracket (1).
  17. Remove the right side spark plugs from cylinders  2,  4 and  6. Refer to Spark Plug Replacement in Engine Controls - 3.8L.

  18. Object Number: 153580  Size: SH
  19. Remove the right engine lift bracket bolt and the nut.
  20. Remove the right engine lift bracket.

  21. Object Number: 371090  Size: SH
  22. Remove the fuel injector sight shield bracket nuts.
  23. Remove the fuel injector sight shield bracket.

  24. Object Number: 97755  Size: SH
  25. Remove the right exhaust manifold bolts and the nuts.
  26. Remove the right exhaust manifold.
  27. Remove the right exhaust manifold gasket.

  28. Object Number: 97750  Size: SH
  29. Remove the upper right exhaust manifold heat shield.

  30. Object Number: 97747  Size: SH
  31. Remove the lower right exhaust manifold heat shield.
  32. If replacing the right exhaust manifold remove the heated oxygen (HO2S) sensor from the right exhaust manifold. Refer to Heated Oxygen Sensor 1 Replacement in Engine Controls - 3.8L.

  33. Object Number: 305693  Size: SH
  34. Remove the exhaust manifold studs if damaged.
  35. Clean and Inspect the right exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection in Engine Mechanical - 3.8L.

Installation Procedure


    Object Number: 305693  Size: SH
  1. Install the exhaust manifold studs if removed.
  2. If replacing the right exhaust manifold, install the heated oxygen (HO2S) sensor to the right exhaust manifold. Refer to Heated Oxygen Sensor 1 Replacement in Engine Controls - 3.8L.

  3. Object Number: 97747  Size: SH
  4. Install the lower right exhaust manifold heat shield.

  5. Object Number: 97750  Size: SH
  6. Install the upper right exhaust manifold heat shield.

  7. Object Number: 97755  Size: SH
  8. Install the new right exhaust manifold gasket.
  9. Install the right exhaust manifold.
  10. Notice: Refer to Fastener Notice in the Preface section.

  11. Install the right exhaust manifold bolts and the nuts.
  12. Tighten
    Tighten the bolts and the nuts to 30 N·m (22 lb ft).


    Object Number: 371090  Size: SH
  13. Install the fuel injector sight shield bracket.
  14. Install the fuel injector sight shield bracket nuts.
  15. Tighten
    Tighten the nuts to 30 N·m (22 lb ft).


    Object Number: 153580  Size: SH
  16. Install the right engine lift bracket.
  17. Install the right engine lift bracket bolt and the nut.
  18. Tighten
    Tighten the bolt and the nut to 30 N·m (22 lb ft).

  19. Install the right side spark plugs to cylinders  2,  4 and  6. Refer to Spark Plug Replacement in Engine Controls - 3.8L.

  20. Object Number: 371512  Size: SH
  21. Install the heated oxygen (HO2S) sensor electrical connector (4) to the engine sight shield bracket (1).
  22. Connect the heated oxygen (HO2S) sensor electrical connector (4).
  23. Return the engine to the original position.
  24. Raise the vehicle.

  25. Object Number: 154806  Size: SH
  26. Install the EGR valve inlet adapter pipe to the right exhaust manifold.
  27. Tighten
    Tighten the bolt to 29 N·m (21 lb ft).


    Object Number: 372626  Size: SH
  28. Install the catalytic converter pipe to the right exhaust manifold.
  29. Install the catalytic converter pipe stud nuts to the right exhaust manifold.
  30. Tighten
    Tighten the exhaust manifold pipe stud nuts to 35 N·m (26 lb ft).

  31. Lower the vehicle.

  32. Object Number: 153576  Size: MH
  33. Install the exhaust crossover bolts to the right exhaust manifold.
  34. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).


    Object Number: 153575  Size: SH
  35. Install the exhaust crossover heat shield.
  36. Install the exhaust crossover heat shield nuts.
  37. Tighten
    Tighten the nuts to 20 N·m (15 lb ft).

  38. Install the engine mount struts. Refer to Engine Mount Strut Replacement - Right Side and Engine Mount Strut Replacement - Left Side in Engine Mechanical - 3.8L.
  39. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
  40. Install the cross vehicle brace. Refer to Cross Vehicle Brace Replacement in Body Front End.

Exhaust Manifold Replacement - Right Side 3.4L

Removal Procedure

  1. Remove the air cleaner intake duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls - 3.4L.
  2. Remove the accelerator cable bracket from the throttle body. Refer to Accelerator Control Cable Bracket Replacement in Engine Controls - 3.4L.
  3. Rotate the engine for service access. Refer to Rotating the Engine for Service Access in Engine Mechanical - 3.4L.
  4. Remove the manifold absolute pressure (MAP) sensor. Refer to Manifold Absolute Pressure Sensor Replacement in Engine Controls - 3.4L.
  5. Remove the exhaust gas recirculation (EGR) pipe. Refer to Exhaust Gas Recirculation Pipe Replacement in Engine Controls - 3.4L.
  6. Remove the ignition module and the ignition coils with the bracket. Refer to Ignition Control Module Replacement in Engine Controls - 3.4L.
  7. Remove the spark plug wires from the right side spark plugs. Refer to Spark Plug Wire Replacement in Engine Controls - 3.4L.

  8. Object Number: 73896  Size: SH
  9. Disconnect the heated oxygen sensor (HO2S) electrical connector.
  10. Remove the evaporative emissions (EVAP) solenoid bracket.
  11. Remove the exhaust crossover pipe nuts from the right 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
  15. Remove the exhaust manifold heat shield bolts.
  16. Remove the exhaust manifold heat shields.

  17. Object Number: 187052  Size: SH
  18. Remove the exhaust manifold nuts.
  19. Remove the exhaust manifold.
  20. Remove the exhaust manifold gasket.
  21. Clean and inspect the right exhaust manifold mating surfaces. Refer to Exhaust Manifold Cleaning and Inspection in Engine Mechanical - 3.4L.
  22. If replacing the right 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. 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.


    Object Number: 187052  Size: SH
  3. Install the exhaust manifold gasket.
  4. Install the exhaust manifold.
  5. Install the exhaust manifold nuts.
  6. Tighten
    Tighten the 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 bolts to 10 N·m (89 lb in).

  11. Install the catalytic converter. Refer to Catalytic Converter Replacement .
  12. Lower the vehicle.
  13. Install the exhaust crossover pipe nuts to the right exhaust manifold. Refer to Exhaust Crossover Pipe Replacement .
  14. Install the EVAP solenoid bracket.

  15. Object Number: 73896  Size: SH
  16. Connect the heated oxygen sensor (HO2S) electrical connector.
  17. Install the spark plug wires to the right side spark plugs. Refer to Spark Plug Wire Replacement in Engine Controls - 3.4L.
  18. Install the ignition module and the ignition coils with the bracket. Refer to Ignition Control Module Replacement in Engine Controls - 3.4L.
  19. Install the EGR pipe. Refer to Exhaust Gas Recirculation Pipe Replacement in Engine Controls - 3.4L.
  20. Install the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement Engine Controls - 3.4L.
  21. Return the engine to the original position.
  22. Install the right and the left engine mount struts. Refer to Engine Mount Strut Replacement - Left Side and Engine Mount Strut Replacement - Right Side in Engine Mechanical  - 3.4L.
  23. Install the accelerator cable bracket to the throttle body. Refer to Accelerator Control Cable Bracket Replacement in Engine Controls - 3.4L.
  24. Install the air cleaner intake duct. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls - 3.4L.