87. Exhaust Manifold Installation - Left

Exhaust Manifold Installation - Left





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 Diagnostic (OBD) II system performance.
- The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or threadlocking material.

Important: Do not apply sealant to the first three threads of the bolt.

1. Apply a 5 mm (0.2 inch) wide band of threadlock GM P/N United States 12345493, GM P/N Canada 10953488, or equivalent, to the threads of the exhaust manifold bolts.
2. Install the exhaust manifold and NEW exhaust manifold gasket.

Notice: Refer to Fastener Notice in Service Precautions.

3. Install the exhaust manifold bolts.
3.1. Tighten the exhaust manifold bolts a first pass to 15 Nm (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.
3.2. Tighten the exhaust manifold bolts a final pass to 25 Nm (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.
4. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the left cylinder head.





5. Install the heat shield (2) and bolts (3).
- Tighten the heat shield bolts to 9 Nm (80 lb in).