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 effect 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.

1. 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.
2. Install the exhaust manifold and NEW exhaust manifold gasket.
   Fig 1: Installing Exhaust Manifold

   Courtesy of GENERAL MOTORS CORP.
   NOTE: Refer to FASTENER NOTICE .
3. Install the exhaust manifold bolts.

   Tighten 

   1. 3.1. 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. 3.2. 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.
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 exhaust manifold heat shield and bolts, if required.

   Tighten 

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

6. Install the air injection reaction (AIR) pipe, with check valve, NEW gasket, and bolts.
   Fig 2: Installing Air Injection Reaction Pipe

   Courtesy of GENERAL MOTORS CORP.

   Tighten 

   Tighten the AIR pipe to exhaust manifold bolts to 20 N.m (15 lb ft).

7. Install the oxygen sensor into the intake manifold.

   Tighten 

   Tighten the oxygen sensor to 42 N.m (30 lb ft).

   Fig 3: Installing Oxygen Sensor Into Intake Manifold

   Courtesy of GENERAL MOTORS CORP.