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 3 threads of the bolt.

Apply a 5 mm (0.2 in) wide band of threadlock GM P/N 12345493 (Canadian P/N 10953488), or equivalent, to the threads of the exhaust manifold bolts. Refer to Sealers, Adhesives, and Lubricants .
Install the exhaust manifold and NEW exhaust manifold gasket.

Fig 1: View Of Exhaust Manifold, Bolts & Gasket (Left)
Courtesy of GENERAL MOTORS CORP.

NOTE: Refer to Fastener Notice .

Install the exhaust manifold bolts.
Tighten:
1. Tighten the exhaust manifold bolts a first pass to 15 N.m (11 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
2. Tighten the exhaust manifold bolts a final pass to 25 N.m (18 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the left cylinder head.
Install the heat shield (603) and bolts (604).

Fig 2: View Of Manifold, Heat Shield & Bolts
Courtesy of GENERAL MOTORS CORP.

Tighten: Tighten the heat shield bolts to 9 N.m (80 lb in).