Compression Check: Testing and Inspection

Compression, Checking

Special tools, testers and auxiliary items required

• Spark Plug Removal Tool (3122B)

• Compression Tester (VAG1763)

• Ignition Coil Puller (T40039)

Work procedure

• Engine oil temperature min. 30 °C.

• Battery voltage min. 12.5 V.

- Switch off ignition.

- Pull rear engine cover off - arrows -.





- Remove cover - 1 - in engine compartment (left side).





- Remove coolant expansion tank - arrow -.





- Disconnect electrical connection from Engine Coolant Level (ECL) Warning Switch (F66) at bottom of coolant reservoir and set aside coolant reservoir with coolant hoses - 1 to 3 - connected.

- Remove cover - 1 - in engine compartment (right side).





- Remove the bolts - arrows -.





- Disengage Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) - 1 - from air duct.

- Remove the air duct - 2 -.

- Remove air filter housing - arrows -.





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

- Disconnect air duct hose - 2 - together with Mass Air Flow (MAF) Sensor (G70).

- Remove screws - 4 - and - 5 - on left cylinder head cover.





- Disconnect electrical harness connectors - 1 to 3 - and - 6 -.

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

- Remove screws - 5 - and - 6 - on right cylinder head cover.





- Disconnect electrical harness connectors - 1 to 4 -.

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

- Using Spark Plug Removal Tool (3122B), remove spark plugs.

- Disconnect electrical connectors to all fuel injectors by releasing connectors at underside - arrow -.





- Check compression using Compression Tester (VAG1763 ).

• Using tester => operating instructions.

- Have a second mechanic 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, noting the following:

- Install sparks plugs.

- After compression pressure test, check DTC memory of Engine Control Module (ECM) and erase, if necessary.