1. Remove the intake manifold. Refer to Intake Manifold Replacement.



2. Remove the valley cover bolts (506).
3. Remove the valley cover (555) and gasket (556).
4. Remove the O-ring seals (537) from the cover.



5. Remove the oil pressure sensor (706) and washer (707) as required.
6. Clean and inspect the engine valley cover. Refer to Engine Block Valley Cover Cleaning and Inspection.

Note: All gasket surfaces should be free of oil or other foreign material during assembly.

1. Lubricate the O-ring seals with clean engine oil.
2. Install the O-rings seals (537) to the cover (555).

Caution: Refer to Fastener Caution in the Preface section.

3. Install the cover (555), gasket (556), and bolts (506). Tighten the manifold bolts to 25 N·m (18 lb ft).



4. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent, to the threads of the sensor.
5. Install the oil pressure sensor (706) and sealing washer (707) and tighten to 35 N·m (26 lb ft).
6. Install the intake manifold. Refer to Intake Manifold Replacement.