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Compression Check: Testing and Inspection






Compression, Checking





Special tools, testers and auxiliary items required

Spark plug removal tool (3122 B)

Puller (T40039)

Torque Wrench (V.A.G 1331)

Compression tester (V.A.G 1763)

Test Sequence

Observe safety precautions => [ Safety Precautions ] Service Precautions.

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

Battery voltage at least 12.7 V

Proceed as follows:

- Remove the engine cover => [ Engine Cover, Removing and Installing ] Engine Cover, Removing and Installing.

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





- Remove the ignition coils with the puller (T40039).





- Remove spark plugs, using spark plug removal tool (3122 B).

- Check compression using compression tester (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 sparks plugs, tightening specification => [ Ignition, Assembly Overview ] Removal and Replacement.

- Install ignition coils with power output stage => [ Ignition Coils with Power Output Stages, Removing and Installing ] Service and Repair.

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

- Read the engine control module DTC memory => vehicle diagnostic tester.