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.

- Remove rear engine cover - arrows -.





- Remove front engine cover.





- 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 hose clamp - 2 - and opening clips - arrows -.

- Remove bolts - arrows -.





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

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





• Ignore items - 1 to 4 -.

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





• Ignore items - 1 to 5 -.

- Remove ignition coils using 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.





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

- Install spark plugs.

- Finally, check DTC memory and, if necessary, erase it. After DTC memory is erased, a readiness code must be generated for the engine control module using operating mode "Guided Fault-finding".

Tightening specifications