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For 1990-2009 cars only

Exhaust Manifold Replacement - Right Side LZ4

Tools Required

J 39194-B Heated Oxygen Sensor Wrench

Removal Procedure


    Object Number: 1523735  Size: SH
  1. Remove the generator. Refer to Generator Replacement .
  2. Remove the connector position assurance (CPA) retainer (2).
  3. Disconnect the heated oxygen sensor (HO2S) electrical connector (1).
  4. Important: The HO2S uses a permanently attached pigtail and connector. This pigtail should not be removed from the sensor. Damage or removal of the pigtail or connector will affect proper operation of the sensor.

  5. Remove the HO2S using the J 39194-B .

  6. Object Number: 1523739  Size: SH
  7. Remove the exhaust gas recirculation (EGR) pipe bolts (3). Reposition the pipe slightly.

  8. Object Number: 1523738  Size: SH
  9. Remove the upper exhaust manifold nuts.
  10. Remove the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side .
  11. Remove the lower exhaust manifold nuts.
  12. Remove the exhaust manifold.
  13. Remove and discard the exhaust manifold gasket.

Installation Procedure


    Object Number: 1523738  Size: SH
  1. Install a NEW exhaust manifold gasket onto the cylinder head studs.
  2. Install the exhaust manifold.
  3. Notice: Refer to Fastener Notice in the Preface section.

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

  6. Install the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side .

  7. Object Number: 1523739  Size: SH
  8. Position the EGR pipe as necessary, and install the EGR pipe bolts (3).
  9. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1523735  Size: SH

    Important: Whenever the oxygen sensor is removed, coat the threads with nickel-based anti-seize compound such as GM P/N 5613695, or equivalent.

  10. Install the HO2S using J 39194-B .
  11. Tighten
    Tighten the sensor to 42 N·m (31 lb ft).

  12. Connect the HO2S electrical connector (1).
  13. Install the CPA retainer (2).
  14. Ensure that the connector rosebud is attached to the bracket.
  15. Install the generator. Refer to Generator Replacement .

Exhaust Manifold Replacement - Right Side LZ9 w/RPO MT2

Tools Required

J 39194-B Heated Oxygen Sensor Wrench

Removal Procedure


    Object Number: 1684189  Size: SH
  1. Remove the generator. Refer to Generator Replacement .
  2. Remove the connector position assurance (CPA) retainer (5).
  3. Disconnect the engine harness electrical connector (4) heated oxyygen sensor (HO2S) electrical connector (4).
  4. Remove the HO2S clip (3) from the oil level indicator tube bracket.

  5. Object Number: 1684191  Size: SH

    Important: The HO2S uses a permanently attached pigtail and connector. This pigtail should not be removed from the sensor. Damage or removal of the pigtail or connector will affect proper operation of the sensor.

  6. Remove the HO2S using the J 39194-B .

  7. Object Number: 1585279  Size: SH
  8. Remove the exhaust manifold shield bolts.
  9. Remove the exhaust manifold shield.

  10. Object Number: 1585290  Size: SH
  11. Remove the upper exhaust manifold bolts.
  12. Remove the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side .
  13. Remove the lower exhaust manifold bolt.
  14. Remove the exhaust manifold.
  15. Remove and discard the exhaust manifold gasket.

Installation Procedure


    Object Number: 1585290  Size: SH
  1. Install a NEW exhaust manifold gasket onto the cylinder head studs.
  2. Install the exhaust manifold.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the exhaust manifold bolts.
  5. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).

  6. Install the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side .

  7. Object Number: 1585279  Size: SH
  8. Install the exhaust manifold shield.
  9. Install the exhaust manifold shield bolts.
  10. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1684191  Size: SH

    Important: Whenever the oxygen sensor is removed, coat the threads with nickel-based anti-seize compound such as GM P/N 5613695, or equivalent.

  11. Install the HO2S using J 39194-B .
  12. Tighten
    Tighten the sensor to 42 N·m (31 lb ft).


    Object Number: 1684189  Size: SH
  13. Connect the engine harness electrical connector (4) to the HO2S electrical connector (4).
  14. Install the CPA retainer (5).
  15. Install the HO2S clip (3) to the oil level indicator tube bracket.
  16. Install the generator. Refer to Generator Replacement .

Exhaust Manifold Replacement - Right Side LZ9 w/RPO M15

Tools Required

J 39194-B Heated Oxygen Sensor Wrench

Removal Procedure


    Object Number: 1583636  Size: SH
  1. Remove the generator. Refer to Generator Replacement .
  2. Remove the connector position assurance (CPA) retainer (2).
  3. Disconnect the heated oxygen sensor (HO2S) electrical connector (1).
  4. Remove the HO2S clip from the ignition control module bracket.

  5. Object Number: 1585927  Size: SH

    Important: The HO2S uses a permanently attached pigtail and connector. This pigtail should not be removed from the sensor. Damage or removal of the pigtail or connector will affect proper operation of the sensor.

  6. Remove the HO2S using the J 39194-B .

  7. Object Number: 1585295  Size: SH
  8. Remove the exhaust manifold shield bolts.
  9. Remove the exhaust manifold shield.

  10. Object Number: 1585309  Size: SH
  11. Remove the upper exhaust manifold bolts.
  12. Remove the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side .
  13. Remove the lower exhaust manifold bolt.
  14. Remove the exhaust manifold.
  15. Remove and discard the exhaust manifold gasket.

Installation Procedure


    Object Number: 1585309  Size: SH
  1. Install a NEW exhaust manifold gasket onto the cylinder head studs.
  2. Install the exhaust manifold.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the exhaust manifold bolts.
  5. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).

  6. Install the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side .

  7. Object Number: 1585295  Size: SH
  8. Install the exhaust manifold shield.
  9. Install the exhaust manifold shield bolts.
  10. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1585927  Size: SH

    Important: Whenever the oxygen sensor is removed, coat the threads with nickel-based anti-seize compound such as GM P/N 5613695, or equivalent.

  11. Install the HO2S using J 39194-B .
  12. Tighten
    Tighten the sensor to 42 N·m (31 lb ft).


    Object Number: 1523735  Size: SH
  13. Connect the HO2S electrical connector (1).
  14. Install the CPA retainer (2).
  15. Install the HO2S clip to the ignition control module bracket.
  16. Install the generator. Refer to Generator Replacement .

Exhaust Manifold Replacement - Right Side LY7

Removal Procedure

Caution: Refer to Exhaust Service Caution in the Preface section.

Caution: Refer to Protective Goggles and Glove Caution in the Preface section.


    Object Number: 1838537  Size: SH
  1. Remove the catalytic converter. Refer to Catalytic Converter Replacement - Right Side .
  2. Remove the exhaust manifold lower bolts.
  3. Lower the vehicle half way.

  4. Object Number: 1838540  Size: SH
  5. Remove the exhaust manifold upper bolts.

  6. Object Number: 1838541  Size: SH
  7. Remove the exhaust manifold.

  8. Object Number: 1838542  Size: SH
  9. Remove and discard the exhaust manifold gasket.

Installation Procedure


    Object Number: 1836986  Size: SH
  1. Install one upper exhaust manifold bolt (1) to the exhaust manifold.
  2. Place the NEW exhaust manifold gasket onto the bolt.
  3. Position and install the exhaust manifold (with gasket) to the cylinder head.

  4. Object Number: 1838540  Size: SH
  5. Loosely install the remaining upper exhaust manifold bolts.
  6. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

  7. Object Number: 1838537  Size: SH
  8. Loosely install the lower exhaust manifold bolts.
  9. Notice: Refer to Fastener Notice in the Preface section.

  10. Tighten the exhaust manifold bolts.
  11. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).

  12. Install the catalytic converter. Refer to Catalytic Converter Replacement - Right Side .