Misfiring causes irregularities in the rotational speed of the crankshaft. These irregularities can be detected by way if changes in the segment time.
Segment times (time, in which a certain number of teeth on the increment wheel move past the sensor) are constantly determined via the reference mark sensor (= crankshaft sensor). These segment times are constantly checked during engine operation. In the event of a fault, a defect code is stored and injection of the corresponding cylinder is deactivated.
Note
Sensor wheel adaptation must be carried out after replacing a DME control module or increment wheel. If only the increment wheel is replaced, the sensor-wheel adaptation must first be deleted (disconnect control module from power supply for 5 minutes). Sensor wheel adaptation is implemented automatically as soon as the engine is operated in overrun condition for at least 10 seconds. See sensor-wheel adaptation.