Audi Workshop Service and Repair Manuals

Identify an inoperative or misfiring cylinder as follows:

• ‒ Disconnect the connectors from the injectors in sequence with the engine running, and observe how the engine runs.

• or

• ‒ Compare the spark plugs of all cylinders with each other and check for soot on the electrodes.

If the defective cylinder has been identified:

• ‒ Connect multimeter to spark plug connector for resistance measurement.

• Specified result: approx. 2 kω

If specified result is not attained:

• ‒ Renew the spark plug connector.

If specified result is attained:

• ‒ Replace the spark plug of the defective cylinder with one from another cylinder.

If the fault moves with the spark plug:

• ‒ Renew the spark plug.

If the fault remains in the same cylinder:

• ‒ Replace the ignition coil from the defective cylinder with one from another cylinder.

If the fault moves with the ignition coil:

• ‒ Renew the ignition coil.

If the fault remains in the same cylinder:

• ‒ Disconnect the connector from the ignition coil.

• ‒ → Check the earth connection from contact 4a to the engine earth for an open circuit or short to positive.
• ‒ Rectify short circuit or open circuit if necessary.

If the earth connection is OK:

• ‒ → Connect the multimeter for voltage measurement to contact 15 on the connector and to earth.

• Specified result: approx. battery voltage.

If specified result is not attained:

• ‒ Check the wiring connections.

=> Circuit diagrams, Electrical Fault Finding and Installation Location binder

If specified result is attained:

• ‒ Remove the 4-pin connector from the power output stage => Overview of installations locations - Page 24-4.
• ‒ Switch the ignition on.

• ‒ → Connect the V.A.G 1527 diode test lamp to the following contacts on the connector:

If the specified results are not obtained:

• ‒ Switch off ignition.

The following wiring connections should be checked for open circuits and/or short to positive or negative:

• ‒ Rectify short circuit or open circuit if necessary.