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Compression Check: Testing and Inspection


Compression pressure, checking





Special tools and equipment
^ 3122B spark plug removal tool
^ VAG1331 torque wrench (5 to 50 Nm)
^ VAG1763 compression tester

Test requirements
^ Engine oil temperature must be at least 30°C.
^ Voltage supply OK

Procedure





- Remove fuse 32 from fuse holder.

Note: By removing fuse 32, voltage supply to the fuel injectors is interrupted.

- Disconnect connectors for ignition coils.
- Remove ignition coils, Refer to Powertrain Management.

- Unscrew spark plugs using 3122B spark plug removal tool.
- Have a second technician depress accelerator pedal completely.
- Test engine compression using VAG1381 or VAG1763 compression tester.

Note: Using VAG1381 or VAG1763 compression tester = operating instructions.

- Have a second technician operate the starter.
- Activate starter until no further pressure increases are indicated by VAG1381 or VAG1763 compression tester.

Compression values:
New: 10 to 14 bar positive pressure, Wear limit: 7.0 bar positive pressure
Tolerated deviation between cylinders: maximum 3 bar
- install spark plugs and ignition coils.
- Check DTC memory: Refer to Powertrain Management.