Checking compression

Special tools and workshop equipment required

• Spark plug socket - 3122 B-

• Compression tester - V.A.G 1763-

Procedure

• Engine oil temperature at least 30 °C.
• Battery voltage at least 12.5 V.

• Remove fuse for fuel pump control unit from fuse holder. Fuse assignment ⇒ Current flow diagrams, Electrical fault finding and Fitting locations

• Start engine and allow it to run until the engine turns off.
• Switch off ignition.
• Remove resonator for intake air ⇒ 3.3 Removing and installing resonator for intake air.

• Pull off connector -2- and unscrew bolt -1-.
• Pull out ignition coils with output stages.
• Unscrew spark plugs using spark plug socket and extension - 3122 B-.
• Check compression pressure using compression tester - V.A.G 1763-; refer to ⇒ Operating instructions.
• Get a second mechanic to press down the accelerator pedal.
• Simultaneously operate starter until tester shows no further pressure increase.
• Repeat procedure on each cylinder.

Installing

Assembly is carried out in reverse sequence; note the following:

• Install spark plugs. Specified torque 22 Nm.
• Install ignition coils with output stages ⇒ 1.2 Removing and installing ignition coils with output stage.
• Entries will have been made in the event memory of the engine control unit because connectors were separated and the engine was started.
• Carry out the function Generate readiness code on ⇒ Ve‐