Compression Check: Testing and Inspection

Compression Pressure, Measuring

Special tools, testers and auxiliary items required

• Spark Plug Removal Tool (3122 B)

• Compression Tester (V.A.G 1763)

• Ignition Coil Puller (T40039)

Procedure

• Engine oil temperature at least 30° C.

• Battery voltage at least 12.5 V.

- Switch off ignition.

- Remove Engine Control Module (ECM) (J623).

- Only remove smaller connector - 1 - from engine control module (ECM) by removing connector lock - arrow -.





• The larger connector - 2 - remains connected.

- Free up fuel line and line to EVAP canister on air guide pipe.





- Disconnect electrical harness connector - 1 - at Mass Air Flow (MAF) Sensor (G70).

- Remove vacuum line - 4 - to air guide hose from suction jet pump.

- Remove oil dipstick - 1 - from guide tube.





- Remove bolts - 2 and 3 -.

- Disconnect electrical harness connectors at ignition coils.

- Press electrical wiring harness to side.

- Remove bolts - 1 and 2 -.





- Disconnect electrical harness connectors at ignition coils.

- Press electrical wiring harness to side.

- Remove all ignition coils using Ignition Coil Puller (T40039).





- Remove spark plugs using Spark Plug Removal Tool (3122 B).

- Check compression using Compression Tester (V.A.G 1763).

• Using tester. Refer to the Operating Instructions.

- Have a second technician press accelerator pedal completely and at the same time operate starter long enough until pressure increase no longer appears on tester.





Assembly is performed in reverse order of removal, note the following:

- Install sparks plugs.

- Install Engine Control Module (ECM) (J623).

Faults are saved in ECM when electrical connectors are disconnected:

- Connect Vehicle Diagnosis, Testing & Info. System (VAS5051B).

- Start "Guided Functions" operating mode.

- Generate readiness code in ECM.