Compression Check: Testing and Inspection

Compression, Checking

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 min. 30 °C

• Battery voltage at least 12.5 V.

- Switch off ignition.

- Pull rear engine cover off - arrows -.





- Pull front engine cover off - arrows -.





- 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 - and - 2 - connected.

- Disconnect check valve - 1 - from connection at air duct hose.





- Remove air duct hose, thereby loosening the hose clamp - 2 - and opening the clips - arrows -.

- Remove bolts - arrows -.





- Remove air duct - 1 - and - 2 -.

- Remove the bolts - arrows - and separate the electrical connections at the ignition coils of left cylinder head.





• Ignore items - 1 to 4 -.

- Remove bolts - arrows - and separate the electrical connections at the ignition coils of right cylinder head.





• Ignore items - 1 to 5 -.

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





- On rear of left cylinder head, disconnect electrical harness connector - 3 - for fuel injectors.





• Ignore - 1 -, - 2 - and - arrow -.

- On rear of right cylinder head, disconnect electrical harness connector - 1 - for fuel injectors.





• Disregard - arrow -.

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

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

• Using tester => 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.

- Repeat procedure on each cylinder.





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

- Install spark plugs.

- Faults have been stored in the engine control modules because the connectors were disconnected: perform a "generate readiness code" under "Guided Functions".

Tightening Specifications