Removal Procedure
- Raise and suitably support the vehicle. Refer to 
Lifting and Jacking the Vehicle .
 
- Remove the exhaust manifold pipe nuts.
 
- Lower the vehicle.
 
- Remove the spark plug wires. Refer to 
Spark Plug Wire Replacement .
 
- Remove the exhaust manifold bolts, manifold, and gasket.
 
- Discard the gasket.
 
- Remove the heat shield bolts (3), and shield (2) from the exhaust manifold (1), if necessary.
 
Installation Procedure
Notice: Refer to Fastener Notice in the Preface section.
- Install the heat shield (2), and bolts (3) to the exhaust manifold (1), if necessary.
 
Tighten
Tighten the bolts to 9 N·m (80 lb in).
Important: 
|    •  | Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may affect vehicle emissions and/or On-Board Diagnostics (OBD) II system performance. | 
 
|    •  | The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or threadlocking material. | 
 
|    •  | Do not apply sealant to the first three threads of the bolt. | 
 
- Apply a 5 mm (0.2 in) wide band of threadlock GM P/N 12345493 (Canadian P/N 101953488) or equivalent to the threads of the exhaust manifold bolts.
 
- Install the exhaust manifold, NEW gasket and bolts.
 
Tighten
- Tighten the exhaust manifold bolts a first pass to 15 N·m (11 lb ft). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
 
- Tighten the exhaust manifold bolts a final pass to 25 N·m (18 lb ft). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
 
- Install the spark plug wires. Refer to 
Spark Plug Wire Replacement .
 
- Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the left cylinder head.
 
- Raise the vehicle.
 
- Install the exhaust manifold pipe nuts.
 
Tighten
Tighten the nuts to 50 N·m (37 lb ft).
- Lower the vehicle.