For 1990-2009 cars

### Removal Procedure

1. Disconnect the 4 ignition coils.
2. Remove the 4 ignition coils (1).
3. Remove the accelerator cable from the clip on the cylinder head cover.
4. Remove the oil level gauge.
5. Remove the positive crankcase ventilation (PCV) hose.
6. Remove the positive crankcase ventilation (PCV) breather hose.
7. Remove the 6 cap nuts and washers from the cylinder head.
8. Remove the cylinder head cover (1).
9. Remove the cylinder head cover gasket (2).
10. Remove the 4 O-rings (3).

### Installation Procedure

Important: Use a new cylinder head cover gasket, new O-rings and a new side seal whenever the cylinder head cover replacement procedure is performed.

1. Ensure that the new gasket, the new O-rings and the new side seal are correctly positioned during the cylinder head cover installation.
2. Clean the sealing surfaces on the cylinder head cover and the cylinder head.
3. Apply GM P/N 12346240 or equivalent to the cylinder head at the points indicated (1).
4. Install the 4 new O-rings (3) to the cylinder head cover (1).
5. Install the new cylinder head cover gasket (2) to the cylinder head cover.
6. Install the new cylinder head side seal (4) to the cylinder head.
7. Install the cylinder head cover to the cylinder head.

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.

8. Install new washers to the cylinder head cover and install the cap nuts.

Tighten
Starting in the center, cross-tighten the cylinder head cover nuts evenly to 11 N·m (97 lb in).

9. Install the 4 ignition coils (1).
10. Connect the 4 ignition coils.
11. Install the accelerator cable to the clip on the cylinder head cover.
12. Install the oil level gauge.
13. Install the positive crankcase ventilation (PCV) hose.
14. Install the PCV breather hose.