Exhaust Manifold Replacement - Right Side

Exhaust Manifold Replacement - Right Side (LZ4) (3.5L)

Special Tools

J 39194-B Heated Oxygen Sensor Wrench

Removal Procedure




1. Remove the generator. Refer to Generator Replacement (LE5 or LE9) Generator ReplacementGenerator Replacement (LZ4 or LZE) Generator ReplacementGenerator Replacement (LY7) Generator ReplacementGenerator Replacement (LZ9) Generator Replacement.
2. Remove the connector position assurance (CPA) retainer (2).
3. Disconnect the heated oxygen sensor (HO2S) electrical connector (1).

Note: 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 upper exhaust manifold nuts.
7. Remove the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side (LY7) Catalytic Converter Replacement - Right SideCatalytic Converter Replacement - Right Side (LZ4) Catalytic Converter Replacement - Right SideCatalytic Converter Replacement - Right Side (LZ9 w/RPO M15) Catalytic Converter Replacement - Right Side (M15)Catalytic Converter Replacement - Right Side (LZ9 w/RPO MT2) Catalytic Converter Replacement - Right Side (MT2).
8. Remove the lower exhaust manifold nuts.
9. Remove the exhaust manifold.
10. Remove and discard the exhaust manifold gasket.

Installation Procedure




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

Caution: Refer to Fastener Caution Fastener Caution.

3. Install the exhaust manifold nuts.

Tighten the nuts to 16 Nm (12 lb ft).

4. Install the right catalytic converter. Refer to Catalytic Converter Replacement - Right Side (LY7) Catalytic Converter Replacement - Right SideCatalytic Converter Replacement - Right Side (LZ4) Catalytic Converter Replacement - Right SideCatalytic Converter Replacement - Right Side (LZ9 w/RPO M15) Catalytic Converter Replacement - Right Side (M15)Catalytic Converter Replacement - Right Side (LZ9 w/RPO MT2) Catalytic Converter Replacement - Right Side (MT2).




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

Tighten the bolts to 10 Nm (89 lb in).





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

6. Install the HO2S using J 39194-B .

Tighten the sensor to 42 Nm (31 lb ft).

7. Connect the HO2S electrical connector (1).
8. Install the CPA retainer (2).
9. Ensure that the connector rosebud is attached to the bracket.
10. Install the generator. Refer to Generator Replacement (LE5 or LE9) Generator ReplacementGenerator Replacement (LZ4 or LZE) Generator ReplacementGenerator Replacement (LY7) Generator ReplacementGenerator Replacement (LZ9) Generator Replacement.