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Oil Pressure Diagnosis and Testing



Oil Pressure Diagnosis and Testing

Tools Required

J-21867-850 Oil Pressure Gage Adapter

* 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 J-21867-850 and 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
- 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