GM Service Manual Online
For 1990-2009 cars only
    • Low oil level. Fill to full mark on oil level indicator.
    • Incorrect or malfunctioning oil pressure switch
    • Incorrect or malfunctioning oil pressure gauge
    • Improper oil viscosity for the expected temperature
    • Oil pump worn or dirty
    • Malfunctioning oil pump pressure regulator valve
    • Plugged oil filter
    • Oil pump screen loose plugged, or damaged
    • Excessive bearing clearance. Replace as necessary.
    • Cracked, porous or restricted oil galleries. Repair or replace block.
    • Oil gallery plugs missing or incorrectly installed. Install plugs or repair as necessary.
    • Oil diluted by moisture or unburned fuel