Checking oil pressure and pressure sensor (VW Polo 3)

1. Unscrew the pressure sensor and screw it into the tester (Fig. 7.31).



2. Screw the tester adapter into the hole for the pressure sensor in the cylinder head.

3. Connect the brown tester wire to the "-" (ground).

4. Connect the VAG 1527 diode tester with an additional wire to the "+" of the battery and the pressure sensor terminal. The tester light should not light up.

5. If the light comes on, replace the 0.7 bar pressure sensor.

6. If the light does not come on, start the engine and slowly increase the engine speed. At a pressure of 0.55-0.85 the light should come on, otherwise replace the sensor.

7. Slowly increase engine speed. At 2000 rpm and 80°C the pressure should be 2.0 bar. At high crankshaft speeds the oil pressure should not exceed the limit of 7 bar. If necessary, replace the oil pump cover with bypass valve.