Compression, Checking
Special tools and workshop equipment required
- Spark Plug Removal Tool: 3122B
- Compression Tester Kit: VAG1763
- Adapter: VAG1763/13 , not illustrated
Test Sequence
- Engine oil temperature at least 30 °C (86 °F)
- Battery voltage at least 12.7 V.
-- Remove the engine cover. Refer to ENGINE COVER, REMOVING AND INSTALLING .
-- Disconnect the fuel injector connector -arrow-.
-- Remove the ignition coils. Refer to IGNITION COILS, REMOVING AND INSTALLING .
-- Remove the spark plugs using the Spark Plug Removal Tool: 3122B .
-- Install the Adapter: VAG1763/13 as shown in the respective spark plug hole and connect the Compression Tester Kit: VAG1763 .
-- Check the compression using the Compression Tester Kit: VAG1763 . Refer to the Operating Manual.
-- Have a second technician press the accelerator pedal all the way down and operate the starter at the same time, until a pressure increase is no longer displayed on the tester.
-- Repeat the procedure on each cylinder.
| Compression Pressure | Pressure |
|---|---|
| New | 16.0 to 19.0 bar (232.06 to 275.57 psi) |
| Wear limit | 12.0 bar (174.04 psi) |
| Maximum difference between cylinders | 3.0 bar (43.51 psi) |
TIP:
If the test with the Compression Tester Kit: VAG1763 does not lead to a clear result there are two additional tests.
- In addition to the compression test a pressure test can be performed with the Pressure-Loss Tester: VAS522001 . The procedure for this is described in the operating instructions for the Pressure-Loss Tester: VAS522001 .
- As an additional test the CO2 content in the coolant expansion tank can be measured. A raised CO2 content in the cooling system indicates a leak between the combustion chamber and the cooling system. The CO2 content can be determined using the CO2 Coolant Tester: VAS531009 . The procedure for this is described in the operating instructions of the CO2 Coolant Tester: VAS531009 .
Assembling
-- Install the spark plugs. Refer to OVERVIEW - IGNITION SYSTEM .
-- Install the ignition coils. Refer to IGNITION COILS, REMOVING AND INSTALLING .
-- Install the engine cover. Refer to ENGINE COVER, REMOVING AND INSTALLING .
-- Delete the DTC memory entries in the Engine/Motor Control Module that have occurred during the test using the.