Compression Check: Testing and Inspection
Compression, Checking
Special tools, testers and auxiliary items required
• Spark plug removal tool (3122 B)
• Puller (T10112)
• Torque wrench (V.A.G 1331)
• Compression tester (V.A.G 1763)
Test Conditions
• Engine oil temperature must be at least 30 °C.
• Voltage supply OK.
• All electrical consumers such as, e.g. lights and rear window heater, must be switched off.
• If vehicle is equipped with an A/C system, it must be switched off.
• For vehicles with automatic transmission, selector lever must be in position "P" or "N".
Perform the following:
- Disconnect the connector - arrow - from the ignition coil.
- Disconnect the connectors from the outer fuel injectors.
- Remove the spark plug wires using the extractor (T10112).
- Remove the spark plugs with spark plug removal tool (3122 B).
- Check compression using compression tester (V.A.G 1763) and adapter (V.A.G 1763/6).
• Using tester => operating instructions.
- Have a second technician operate the starter.
- Operate starter until tester shows no further pressure increase.
Compression pressure:
- Check the engine control module DTC memory and correct any faults. Then erase the DTC memory. Refer to => [ Engine Control Module DTC Memory, Checking and Erasing ] Engine Control Module DTC Memory, Checking and Erasing.