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Compression Check: Testing and Inspection


Compression pressure, checking





Special tools and equipment
^ 3220 Hinged socket
^ VAG 1331 Torque wrench: 5 to 50 Nm (3 7 to 37 ft. lbs.)
^ VAG 1381/12 Adaptor
^ VAG 1763 Compression tester

Requirement
^ Engine oil temperature must be 30°C minimum.

Test sequence
- Disconnect fuel cut-off valve on Diesel injection pump.
- Disconnect Quantity adjuster harness connector on Diesel injection pump.
- Remove all glow plugs using 3220 flexible wrench.





- Screw in VAG 1381/12 adaptor in place of glow plugs.
- Check compression using VAG 1763 compression tester.
- Operate starter until tester display shows no further increase.

Compression pressure:
^ New: 25 to 31 bar
^ Wear limit: 19 bar

Permissible difference between all cylinders:
^ 5 bar
^ Install glow plugs using 3220 flexible wrench
^ Tightening torque: 15 Nm (11 ft. lbs.)

- Check Diagnostic Trouble Code (DTC) memory:

Note: Trouble codes will be stored because the Diesel injection pump harness connector has been disconnected. Check and erase DTC memory.