For 1990-2009 cars

1. Install the drain plug in the water pump.
2. Apply GM P/N 12346004 (Canadian P/N 10953480), or equivalent, to the plug before installation.

Caution: Refer to Fastener Caution in the Preface section.

3. Install the coolant jacket plugs and tighten to 35 N·m (26 lb ft).
4. Install the rear oil passage plugs.
5. Apply GM P/N 12346004 (Canadian P/N 10953480), or equivalent, to the plugs before installation. Tighten the oil passage plug to 60 N·m (44 lb ft).
6. Install the other oil passage plugs.
7. Apply GM P/N 12346004 (Canadian P/N 10953480), or equivalent, to the plug before installation. Tighten the oil passage plugs to 35 N·m (26 lb ft).
8. Lubricate the crankshaft position (CKP) sensor O-ring with clean engine oil.
9. Install the CKP sensor and bolt and tighten to 10 N·m (89 lb in).
10. Install the oil pressure switch and tighten to 26 N·m (19 lb ft).
11. Install the knock sensors and bolts. Tighten the knock sensor bolts to 25 N·m (18 lb ft).
12. Install the piston oil nozzle assemblies.
13. Install the piston oil nozzle assembly bolts and tighten to 15 N·m (11 lb ft).