- With the vehicle on a level surface, allow adequate drain down
time (2-3 minutes) and measure for a low engine oil level.
Add the recommended grade engine oil GM P/N 12345610 or
equivalent, and fill the crankcase until the oil level measures FULL on the
oil level indicator.
- Operate the engine and verify low or no oil pressure on the vehicle
oil pressure gauge or oil indicator light.
Listen for a noisy valve train or knocking noise.
- Inspect for the following:
| • | Engine oil diluted by moisture or unburned fuel mixtures |
| • | Improper engine oil viscosity for the expected temperature |
| • | Incorrect or faulty oil pressure gauge sensor |
| • | Incorrect or faulty oil pressure gauge |
| • | Malfunctioning oil filter bypass valve |
- Remove the oil pressure gauge sensor or another engine block oil
gallery plug.
- Install an oil pressure gauge and measure the engine oil pressure.
- If the engine oil pressure is below specifications, inspect the
engine for one or more of the following:
| • | Malfunctioning oil pump pressure relief valve |
| • | Oil pump screen loose, plugged, or damaged |
| • | Excessive bearing clearance |
| • | Cracked, porous or restricted oil galleries |
| • | Engine block oil gallery plugs missing or incorrectly installed |
