Compression Check: Testing and Inspection

Compression, Checking

Special tools, testers and auxiliary items required

• Spark Plug Removal Tool (3122 B)

• Puller (T40039)

• Torque Wrench (5-50 Nm) (V.A.G 1331)

• Compression Tester (V.A.G 1763)

• Adapter (V.A.G 1763/6)

Test Conditions:

• Engine oil temperature must be at least 30 °C (86 °F).

• Battery voltage at least 12.7 volts.

Test Sequence:

• Follow all safety precautions. Refer to => [ Safety Precautions ] Safety Precautions.

- Remove the ignition coils with the power output stages. Refer to => [ Ignition Coil with Power Output Stage ] Service and Repair.

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

- Check the compression pressure using the compression tester (V.A.G 1763) and the adapter (V.A.G 1763/6).

• Using the tester, refer to the operating instructions.

- Activate the starter until no further pressure increases are indicated by the tester.

Compression Pressure:

• New: 11.0 to 14.0 bar pressure

• Wear limit: 7.0 bar pressure

• Permissible difference between all cylinders: Max. 3 bar

- Install the spark plugs. Refer to => [ Ignition System Component Overview ] Service and Repair.

- Install the ignition coils with power output stages. Refer to => [ Ignition Coil with Power Output Stage ] Service and Repair.

• By disconnecting the connectors, Diagnostic Trouble Codes (DTCs) are stored to memory. After the test, check the fault memory and erase, if necessary.

- Check the Engine Control Module (ECM) DTC memory and erase any entries. Refer to "Guided Function" in the vehicle diagnostic tester.

• If the DTC memory was erased, the readiness code must be generated again. Refer to "Guided Fault Finding" in the vehicle diagnostic tester.