For 1990-2009 cars

Notice: Refer to Fastener Notice in the Preface section.

1. Install NEW exhaust manifold studs, if necessary.

Tighten
Tighten the studs to 10 N·m (89 lb in).

2. Install the exhaust manifold gasket.
3. Install the exhaust manifold and catalytic converter assembly to the cylinder head.
4. Install NEW exhaust manifold to cylinder head retaining nuts finger tight.
5. Tighten the NEW exhaust manifold cylinder head retaining nuts in sequence.

Tighten
Tighten the nuts a second time to 14 N·m (124 lb in).

6. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 12397953.
7. Install the oxygen sensor.

Tighten
Tighten the oxygen sensor to 42 N·m (31 lb ft).

8. Install the block heater and bolt, if equipped.

Tighten
Tighten the bolt to 10 N·m (89 lb in).

9. Install the exhaust manifold heat shield.
10. Install the exhaust manifold heat shield bolts.

Tighten
Tighten the bolts to 23 N·m (17 lb ft).