For 1990-2009 cars

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

1. Install the threaded oil gallery plugs.

Tighten
Tighten the oil gallery plugs to 30 N·m (22 lb ft).

2. Install the remaining oil gallery plugs using GM P/N 12345493 threadlocker or equivalent.
3. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the knock sensor.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

4. Install the knock sensors.

Tighten
Tighten the knock sensors to 18 N·m (13 lb ft).