Table of contents: Checking the oil pressure sensor 0.3… ↓ Checking oil pressure sensors… ↓ Checking oil pressure ↓
The oil pressure sensors for a 4-cylinder engine are located on the oil filter flange, and for a 5-cylinder engine, on the left side of the engine block behind the oil pump.
Check the oil level.
Check that the electrical wires are connected correctly to the sensor.
Checking the oil pressure sensor 0.3 bar
Unscrew the oil pressure sensor 1.8 bar (white insulation) on top of the oil filter flange. On a diesel engine, unscrew the sensor 1.4 bar, on a turbodiesel 0.9 bar (gray insulation).
Instead of the sensor, screw in a pressure gauge.
If a VAG measuring device is used, screw the pressure sensor into the device.
Disconnect the electrical wire from the 0.3 bar pressure sensor (brown insulation) at the bottom of the filter flange. Connect the sensor with the measuring voltage to the positive pole of the battery. The device should show voltage. The control lamp should light up.
Start the engine and slowly increase its speed.
As soon as the pressure gauge shows 0.15-0.45 bar, the device should no longer show voltage, the control lamp should go out. Otherwise, replace the sensor.
Note: If necessary, check the moment of switching on of the pressure sensor at the engine starting speed.
Checking oil pressure sensors 1.8/1.4/0.9 bar
Caution: The described test can only be carried out if the sensor can be screwed into the measuring device.
Connect the measuring device to ground using wire "3".
Connect the plug contact on the sensor wires "1" and the voltage meter "2" to the positive pole of the battery. When the engine is running, there should be no voltage on the device. Otherwise, replace the sensor.
Start the engine and slowly increase the speed.
When the control pressure is reached, the device should show voltage and the lamp should light up.
Checking oil pressure
Start the engine. Increase the speed to 2000 rpm. At an oil temperature of +80°C, the oil pressure at this speed should be at least 2.0 bar.
Low oil pressure indicates worn crankshaft bearings.
Insert the pressure sensor with the sealing ring and tighten to 25 Nm.
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