Oil Pressure Diagnosis and Testing

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 the following:
^ 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 the following:
^ Oil pump worn or dirty
Refer to Oil Pump Disassemble.
^ Oil pump-to-engine front cover bolts loose
Refer to Engine Front Cover and Oil Pump Installation.
^ 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
Refer to Crankshaft and Bearings Cleaning and Inspection.
^ Cracked, porous or restricted oil galleries
^ Oil gallery plugs missing or incorrectly installed
Refer to Engine Block Assemble.
^ Broken lash adjusters