For 1990-2009 cars

1. Clean the oil pump components in cleaning solvent.

Caution: Refer to Safety Glasses Caution in the Preface section.

2. Dry the components with compressed air.
3. Inspect the gears (427, 428) for the following conditions:

• | Scoring

• | Chipping

• | Galling

• | Excessive wear

4. Inspect the oil pump housing (422) for the following conditions:

• | Damaged bolt hole threads

• | Worn oil pump driveshaft bore

• | Scoring or excessive wear within the housing

• | Worn driven gear shaft

5. Inspect for a collapsed pressure relief valve spring.
6. Inspect the pressure relief valve for scoring or wear. The valve should move freely within the bore of the housing.