Crankshaft Position Timing Ring: Adjustments

Sensor-Wheel Adaptation:

Misfiring causes irregularities in the rotational speed of the crankshaft. These irregularities can be detected on the basis of changes in the segment time.

Segment times (time 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 the injection of the corresponding cylinder deactivated. Refer to misfiring detection.

In order to avoid incorrect evaluation, sensor-wheel adaptation must be carried out after replacing a DME control unit or increment wheel. If only the increment wheel is replaced first the sensor-wheel adaptation must be deleted (disconnect control unit from power supply for 5 minutes).

The sensor-wheel adaptation determines the irregularity of the increment wheel and takes it into consideration when evaluating the segment times. Sensor-wheel adaptation is implemented automatically as soon as the engine is operated in overrun condition for at least 10 seconds.