How to perform an oil pressure test
Peter Sitkowski | 14th Feb 2024 | 5 minutes to read
Performing an oil pressure test on your vehicle’s engine can give you valuable information about the health and functionality of your engine’s lubrication system. You’ll be able to detect whether you have low oil pressure, problems with your oil pump, or a clogged oil filter impeding oil flow.
Low pressure can lead to inadequate lubrication in your system, which leads to increased friction, overheating, and ultimately, engine damage. This is very preventable with regular oil pressure testing and performing an oil pressure test is a simple procedure that anyone with a bit of automotive know-how can do.
Below are the main steps to performing an oil pressure test:
- Get the Vehicle Ready & Acquire the Right Tools
- Locating the Oil Pressure Sending Unit
- Removing the Oil Pressure Sending Unit
- Connecting the Oil Pressure Gauge
- Adding Engine Oil
- Starting the Engine
- Recording the Oil Pressure
- Increasing the Engine Revs
- Analysing the Oil Pressure Readings
- Shutting Down the Engine
- Checking for Leaks and Cleaning Up
- Interpreting the Results
- Documenting the Test Results
Tools for the Job:
- A reliable oil pressure gauge
- Wrench set
- Safety goggles
- Gloves
- Recommended engine oil
Get the Vehicle Ready & Acquire the Right Tools
To conduct a precise oil pressure test, the vehicle must be parked on level ground. Engage the parking brake, and if applicable, chalk the wheels to prevent any unintended movement. Allow the engine to cool down before initiating the test to prevent potential burns from hot components.
Before commencing the oil pressure test, ensure the availability of essential tools and materials as listed above.
Locating the Oil Pressure Sending Unit
Identify the location of the oil pressure sending unit in the engine bay. Refer to the vehicle's manual or online resources if uncertain about its precise location. The sending unit is commonly found near the oil filter housing or connected to the engine block.
Removing the Oil Pressure Sending Unit
Use the appropriate wrench from the set to carefully remove the oil pressure sending unit. Exercise caution to prevent damaging the unit or surrounding components. Place a clean rag or towel beneath the sending unit to catch any residual oil that may leak out.
Connecting the Oil Pressure Gauge
Attach the oil pressure gauge securely to the port from which the sending unit was removed. Ensure a snug fit to prevent air leakage during the test. Double-check the gauge connections for any signs of looseness.
Adding Engine Oil
If the engine oil level is low or requires topping up, add the recommended oil as per the vehicle manufacturer's specifications. It's essential to maintain the correct oil level for an accurate pressure reading during the test.
Starting the Engine
Start the vehicle's engine and allow it to idle. Monitor the oil pressure gauge closely as the engine runs. Note the pressure readings displayed on the gauge, which should ideally fall within the manufacturer's specified range for your vehicle.
Recording the Oil Pressure
Record the oil pressure readings at idle speed, making a note of any fluctuations or irregularities observed on the gauge. These readings serve as a vital reference point for determining the engine's oil pressure health.
Increasing the Engine Revs
Gradually increase the engine revs to around 2000-3000 RPM while observing the oil pressure gauge. Take note of any changes in pressure as the engine speed rises. A healthy engine typically exhibits an increase in oil pressure with higher RPMs.
Analysing the Oil Pressure Readings
Compare the recorded oil pressure readings with the manufacturer's specified values for your vehicle. If the observed readings fall outside the recommended range or display significant fluctuations, it may indicate underlying issues requiring further inspection or maintenance.
Shutting Down the Engine
Once the oil pressure test is complete, turn off the engine. Carefully disconnect the oil pressure gauge from the port and reinstall the oil pressure sending unit using the appropriate wrench. Ensure proper tightening to prevent oil leaks.
Checking for Leaks and Cleaning Up
Inspect the area around the oil pressure sending unit for any oil leaks. Wipe off any spilled oil or residue using a clean rag or absorbent material. Dispose of used materials responsibly and safely.
Interpreting the Results
The oil pressure test provides valuable insights into the health of the engine's lubrication system. Normal oil pressure readings indicate a well-functioning system, while abnormal readings may necessitate professional inspection to diagnose and rectify any underlying issues.
Documenting the Test Results
Maintain a record of the oil pressure test results, including the date, recorded readings, and any observations made during the test. This documentation serves as a reference for future maintenance and allows for tracking changes in the engine's oil pressure over time.
Engine Oil at Repco
From Penrite and Castrol through to Nulon and Valvoline, Repco has engine oil that's suitable for your vehicle. We've also got oil filters and cartridges if you need replacements and all the tools you need for your next DIY job.
