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Compression Check: Testing and Inspection






Compression, Checking

Special tools, testers and auxiliary items required

Puller (T10095A)

Torque wrench (5 to 50 Nm) (V.A.G 1331)

Compression tester (V.A.G 1763)

Spark plug removal tool (3122 B)

Assembly tool (T10118)

Test Conditions

Engine oil temperature must be at least 30° C.

Battery voltage must be at least 11.5 V.

All electrical consumers such as, for example, lights and rear window defroster must be switched off.

If the vehicle is equipped with an air conditioning system, this must be switched off.

For vehicles with automatic transmission, selector lever must be in position "P" or "N".

Fuses - 13 - and - 14 - - arrows - must be removed from their sockets.





Test Sequence

- Remove engine cover.

- Remove ignition coils with power output stage --> [ Ignition Coil with Power Output Stage ] Service and Repair.

- Remove spark plugs using spark plug removal tool (3122 B).

- Check compression pressure using the compression tester (V.A.G 1763).

Using the compression tester --> Operating instructions.

- Have a second technician fully depress accelerator pedal and crank engine.

- Operate starter until tester shows no further pressure increase.

Compression Pressure

New: 10 to 13 bar pressure

Wear limit: 7.5 bar pressure

Permissible difference between all cylinders: 3 bar

- Install the spark plugs using the spark plug removal tool (3122B) and tighten to 20 Nm.

After completing installation:

- Connect vehicle diagnosis and service system (VAS 5052).

- Perform vehicle system test "Guided Fault Finding".

- End vehicle system test, this will automatically erase DTC entries which occurred during the assembly.

- Perform test drive.

- Generate readiness code in conjunction with road test.

Observe safety precautions that apply to road tests.

- Then perform vehicle system test again and repair any occurring malfunctions if necessary.