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Compression Check: Testing and Inspection






Compression, Checking

Special tools, testers and auxiliary items required

Spark Plug Removal Tool (3122 B)

Ignition Coil Puller (T40039)

Compression Tester (V.A.G 1763)

Test Sequence

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

Battery voltage at least 12.7 V

- Remove the engine cover - arrows -.






- Remove the bolts on the ignition coil connector strip.

- Release the connector - arrows - and disconnect all the connectors at the same time from the 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 adapter (V.A.G 1763/6).

Using tester: Operating Instructions.

- Operate starter until tester shows no further pressure increase.

Compression Pressure:






- Install the spark plugs.

- Install the ignition coils with output stages.

By separating the connections, DTCs are stored to memory. After the test, check the DTC memory and erase, if necessary.

- Check the engine control module DTC memory using the vehicle diagnosis, testing and information system VAS 5051 under "Guided Fault Finding.