Audi reports that multiple misfires detected on one or more cylinders, and the MIL may flash indicating one or more DTCs. This applies to 2004-2008 A4, 2005-2008 A6 and 2007-2008 A4 Cabriolet vehicles.
The DTCs that may be set (one or multiples) include P0300….P0306 (random/multiple cylinder misfire), P0335 (crankshaft position sensor A, circuit malfunction), P0336 (crankshaft position sensor A, circuit range/performance), P0321 (ignition/distributor engine speed Inp. circuit/range/performance), and P0322 (ignition/distributor engine speed Inp. circuit no signal).
The condition may be caused by a spacer installed between the engine speed sensor and the gearbox.
Locate the engine speed sensor. Remove the spacer from between the sensor and the gearbox. Discard the spacer. Reinstall the engine speed sensor, tightening the mounting bolt to a value of 10 Nm (7.4 ft-lb).
With VAS 5051 or VAS 5052 diagnostic tool connected, check the ECM for DTCs and for misfire detection in measuring value blocks (MVB) 015 and 016. Erase the DTCs.