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Compression Check: Testing and Inspection






Compression Pressure, Checking

Special tools, testers and auxiliary items required

Spark Plug Removal Tool (3122 B)

Ignition Coil Puller (T40039)

Compression Tester (V.A.G 1763)

Adapter (V.A.G 1763/6)

Test Sequence

Engine oil temperature min. 30 °C (86 °F)

Battery voltage at least 12.7 V

- Remove the engine cover - arrows -.






- Disconnect the electrical connectors - arrows - on ignition coils.






- Remove the ignition coils with the (T40039).






- Remove the spark plugs using a (3122 B).

- Check compression using (V.A.G 1763) and (V.A.G 1763/6).

Using the tester, refer to the operating instructions.

- Operate starter until tester shows no further pressure increase.

Compression Pressure






- Install spark plugs.

- Install the ignition coils with output stages.

By separating the connections, Diagnostic Trouble Code (DTCs) are stored to memory. After the test, check the DTC memory and erase, if necessary.

- Check the Engine Control Module (ECM) DTC memory.