Engine Oil Pressure: Testing and Inspection
Oil Pressure and Oil Pressure Switch, Checking
Special tools, testers and auxiliary items required
• Oil Pressure Gauge (V.A.G 1342)
• Voltage Tester (V.A.G 1527 B)
• Connector Test Set (V.A.G 1594 C)
• Socket 24 mm and Jointed Extension (T40175)
• Torque Wrench (5-50 Nm) (V.A.G 1331)
• Vehicle Diagnostic Tester
Test Conditions
• The engine oil level is OK
• The engine oil temperature is at least 80 °C (140 °F) (the coolant fan must start up once).
• For the functional check and servicing of the optical and acoustic oil pressure warning. Refer to and to "Function and Component Selection" in the vehicle diagnostic tester.
Test Sequence
• Tightening specification, refer to => [ Oil Filter Housing/Accessory Bracket Overview ] Service and Repair.
- Disconnect the connector from the oil pressure switch.
- Remove the oil pressure switch - 2 - using the socket 24 mm and jointed extension (T40175) and install it in the oil pressure gauge (V.A.G 1342).
- Install the oil pressure gauge (V.A.G 1342) in place of the oil pressure switch into the bracket.
- Connect the brown wire - 1 - from tester to ground.
- Connect the voltage tester (V.A.G 1527 B) using adapter cables from the connector test set (V.A.G 1594 C) to battery positive (+) and the oil pressure switch.
• The Light Emitting Diode (LED) must not light up.
If the LED lights up:
- Replace the oil pressure switch.
If the LED does not light up:
- Start the engine and slowly increase the engine speed:
• The LED must light up at 1.2 to 1.6 bar positive pressure, otherwise replace the oil pressure switch.
- Increase the engine speed further:
• At 2000 RPM and an oil temperature of 80 °C (140 °F), the oil pressure should be between 2.7 bar and 4.5 bar.
At higher engine speeds the oil pressure must not exceed 7.0 bar
If the specification is not obtained:
- Make sure the strainer inside the oil intake pipe is not contaminated.
• Also, mechanical damage, for example, bearing damage can also be the cause of too low oil pressure.
If no malfunction can be found:
- Replace the oil pump. Refer to => [ Oil Pump ] Oil Pump.
If the specification is exceeded:
- Check the oil passages.