Compression check (VW Polo 3)

4.1. Engines AEY, AFN, ANV, AHU, AKW, ALE

1. Disconnect the wiring connector from the shut-off valve on the high-pressure fuel pump.

2. Disconnect the wiring connector from the fuel injection pump fuel quantity regulator.

3. Remove all glow plugs.

4. Screw the VAG 1381/12 adapter into the glow plug hole (Fig. 6.22). Check the compression using the VAG 1381 or VAG 1763 tester.



New engine compression: 25-31 bar, permissible wear: 19 bar.

Permissible difference between cylinders: 5 bar.

4.2. Engine 1Y

1. Disconnect wiring connector 1 (Fig. 6.23).



2. Disconnect the high-pressure fuel lines from the injectors, unscrew all the injectors and remove the heat shield.



3. Screw the VAG 1323/2A adapter into the injector hole (Fig. 6.24). Install the old heat shield between the adapter and the cylinder head. Check the compression using the VAG 1381 or VAG 1763 tester.



New engine compression: 34 bar, permissible wear: 26 bar.

Permissible difference between cylinders: 5 bar.