Operation CHARM: Car repair manuals for everyone.

Compression Check: Testing and Inspection



Compression pressure, checking





Special tools, testers and auxiliary items required
^ Spark plug removal tool 3122 B
^ Torque wrench V.A.G 1331
^ Compression tester V.A.G 1763
^ Ignition coil puller T40039 (not illustrated)

Requirements
^ Engine oil temperature must be at least 30°C
^ Voltage supply OK

Work sequence





- Remove fuse 32.

Note:
^ Removing fuse 32 interrupts the voltage supply to the injectors.

- Remove engine cover.
- Remove ignition coils as follows:

Engine code APH





- Disconnect 4-pin connector - arrow - from ignition coils.
- Remove securing bolts and remove ignition coils with output stages vertically from spark plugs.

Engine codes AWP, AWV, BKF, BNU





- Disconnect 4-pin connector - 2 - from ignition coils - 1 -.





- Pull ignition coils with final output stages vertically off of spark plugs with ignition coil puller T40039.

Continuation for all engine codes
- Remove spark plugs with spark plug removal tool 3122 B.
- Have a second technician depress accelerator pedal so that throttle valve is fully open.
- Check compression with compression tester V.A.G 1381 or V.A.G 1763.

Note:
^ Using the compression tester Tester operating instructions.

- Operate starter until tester shows no further pressure increase.

Compression pressure
New: 10...13 bar
Wear limit: 7.5 bar

Permissible difference between all cylinders: max. 3 bar
- Install spark plugs with spark plug removal tool 3122 B and tighten to 30 Nm.

Engine code APH
- Install ignition coils and tighten securing bolts to 10 Nm.

Engine codes AWP, AWV, BKF, BNU
- Install ignition coils with spark plug connector on spark plugs.

Continuation for all engine codes
- Interrogate Diagnostic Trouble Code (DTC) memory of engine control module, if necessary, correct malfunction and erase DTC memory.