Compression Check: Testing and Inspection

Compression, Checking

Special tools, testers and auxiliary items required

• Spark Plug Removal Tool (3122 B)

• Puller for Ignition Coil (T10095 A)

• Assembly Tool (T10118)

• Torque Wrench (5-50 Nm) (V.A.G 1331)

• Compression Tester (V.A.G 1763)

Conditions

• Engine oil temperature at least 30 °C (86 °F)

• The battery voltage must be at least 11.5 volts.

• All electrical components such as for example, lights and rear window heater, must be turned off.

• If vehicle is equipped with an Air Conditioning (A/C) system, it must be turned off.

• Selector lever must be in the "P" or "N" position.

Test Sequence

- Remove the fuel pump fuse from the fuse holder.

Voltage supply to the fuel pump is interrupted when the fuse is removed.

- Using the (T10118) on the locking button - arrow - and carefully pull the connector up.





- Slide on the (T10095 A) from the straight side of the connector in the - direction of the arrow - and pull out the ignition coil with power output stage.





- Remove the spark plugs using the (3122 B).

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

• Using the (V.A.G 1763), refer to the operating instructions.

- Let a second mechanic operate the starter until a pressure increase is no longer indicated on the tester.

Compression Pressure:





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

- Install ignition coils with power output stage.

- To install, insert the ignition coil with power output stage into the appropriate spark plug hole so the straight connector sides fit with each other - arrows -.





After the test is completed:

- Connect the vehicle diagnostic tester.

- Perform the vehicle system test, refer to "Guided Fault Finding" in the vehicle diagnostic tester.

- End the vehicle system test, this will automatically erase Diagnostic Trouble Code (DTC) entries which occurred during the assembly.

- Generate a readiness code in conjunction with a road test.

Observe the safety precautions that apply to road tests.

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