Engine Oil Pressure: Testing and Inspection

Oil Pressure Diagnosis and Testing
^ With the vehicle on a level surface, allow adequate drain down time of 2-3 minutes and measure for a low oil level. Add the recommended grade engine oil and fill the crankcase until the oil level measures full on the oil level indicator.
^ Run the engine, and verify low, or no oil pressure on the vehicle gage or light. Listen for a noisy valve train or a knocking noise.
^ Inspect for:
^ Oil diluted by moisture or unburned fuel mixtures
^ Improper oil viscosity for the expected temperature
^ Incorrect or malfunctioning oil pressure sender
^ Incorrect or malfunctioning oil pressure gage
^ Plugged oil filter
^ Malfunctioning oil bypass valve
^ Remove the oil pressure sender or another engine block oil gallery plug.
^ Install an oil pressure gage and measure the engine oil pressure.
^ Compare the readings to specifications.
^ If the engine oil pressure is below specifications, inspect the engine for one or more of these:
^ Oil pump worn or dirty.
^ Oil pump-to-engine front cover bolts loose.
^ Oil pump screen loose, plugged, or damaged
^ Oil pump screen O-ring seal missing or damaged
^ Malfunctioning oil pump pressure regulator valve
^ Excessive bearing clearance.
^ Cracked, porous or restricted oil galleries
^ Oil gallery plugs missing or incorrectly installed.
^ Broken lash adjusters