Oil Pressure Diagnosis And Testing

Special Tools

• EN-21867-850  Oil Pressure Gauge Adapter
• GE-21867-A  Oil Pressure Gauge Kit

For equivalent regional tools, refer to Special Tools .

1. 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.

2. Run the engine, and verify low, or no oil pressure on the vehicle gauge or light.

   Listen for a noisy valve train or a knocking noise.

3. Inspect for the following:
   • Correct oil filter with anti-drain back feature and O-ring on the cylinder block side of the filter
   • 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 gauge
   • Plugged oil filter
   • Malfunctioning oil bypass valve
4. Remove the oil pressure sender or another engine block oil gallery plug.
5. Install EN-21867-850  adapter and GE-21867  gauge and measure the engine oil pressure.
6. Compare the readings to specifications. Refer to Engine Mechanical Specifications .
7. If the engine oil pressure is below specifications, inspect the engine for one or more of the following:
   • Correct oil filter with anti-drain back feature and O-ring on the cylinder block side of the filter
   • Oil pump worn or dirty

     Refer to Balancer Shaft with Oil Pump Cleaning and Inspection .

   • Oil pump screen loose, plugged, or damaged
   • Oil pump screen O-ring seal missing or damaged
   • Malfunctioning oil control valve solenoid
   • Excessive bearing clearance

     Refer to Crankshaft and Bearing Cleaning and Inspection .

   • Cracked, porous or restricted oil galleries
   • Oil gallery plugs missing or incorrectly installed

     Refer to Engine Block Assemble .

   • Broken lash adjusters