Exhaust Manifold Replacement - Right Side LX9

Tools Required

J 39194-B Heated Oxygen Sensor Socket

1. Remove the generator. Refer to Generator Replacement in Engine Electrical.
2. Remove the connector position assurance (CPA) retainer.
3. Disconnect the heated oxygen sensor (HO2S) electrical connector.

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.

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



5. Remove the exhaust gas recirculation (EGR) pipe bolts (3). Reposition the pipe slightly.
6. Remove the spark plugs. Refer to Spark Plug Replacement in Engine Controls - 3.5L (LX9).
7. Remove the rear catalytic converter. Refer to Catalytic Converter Replacement .



8. Remove the exhaust manifold nuts.
9. Remove the exhaust manifold.
10. Remove and discard the exhaust manifold gasket.

1. Install a NEW exhaust manifold gasket onto the cylinder head studs.
2. Install the exhaust manifold.

Notice: Refer to Fastener Notice in the Preface section.

3. Install the exhaust manifold nuts.

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

4. Install the rear catalytic converter. Refer to Catalytic Converter Replacement .
5. Install the spark plugs. Refer to Spark Plug Replacement in Engine Controls - 3.5L (LX9).



6. Position the EGR pipe as necessary, and install the EGR pipe bolts (3).

Tighten
Tighten the bolts to 10 N·m (89 lb in).





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

7. Install the HO2S using J 39194-B .

Tighten
Tighten the sensor to 42 N·m (31 lb ft).

8. Connect the HO2S electrical connector.
9. Install the CPA retainer.
10. Ensure that the connector rosebud is attached to the bracket.
11. Install the generator. Refer to Generator Replacement in Engine Electrical.

Exhaust Manifold Replacement - Right Side LZ9

Tools Required

J 39194-B Heated Oxygen Sensor Wrench

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.




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. Remove the exhaust manifold shield bolts.
7. Remove the exhaust manifold shield.



8. Remove the upper exhaust manifold bolts.
9. Remove the rear catalytic converter. Refer to Catalytic Converter Replacement .
10. Remove the lower exhaust manifold bolt.
11. Remove the exhaust manifold.
12. Remove and discard the exhaust manifold gasket.

1. Install a NEW exhaust manifold gasket onto the cylinder head studs.
2. Install the exhaust manifold.

Notice: Refer to Fastener Notice in the Preface section.

3. Install the exhaust manifold bolts.

Tighten
Tighten the bolts to 20 N·m (15 lb ft).

4. Install the rear catalytic converter. Refer to Catalytic Converter Replacement .



5. Install the exhaust manifold shield.
6. Install the exhaust manifold shield bolts.

Tighten
Tighten the bolts to 10 N·m (89 lb in).





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

7. Install the HO2S using J 39194-B .

Tighten
Tighten the sensor to 42 N·m (31 lb ft).




8. Connect the HO2S electrical connector (1).
9. Install the CPA retainer (2).
10. Install the HO2S clip to the ignition control module bracket.
11. Install the generator. Refer to Generator Replacement .