Nubira SX Hatchback L4-2.0L DOHC D-TEC MFI (1999)
Crankshaft Position Sensor: Description and Operation
CRANKSHAFT POSITION SENSOR
This direct ignition system uses a magnetic crankshaft position sensor. This sensor protrudes through its mount to within approximately 1.3 mm (0.05
inch) of the crankshaft reluctor. The reluctor is a special wheel attached to the crankshaft or crankshaft pulley with 58 slots machined into it, 57 of which
are equally spaced in 6 degree intervals. The last slot is wider and serves to generate a "sync pulse." As the crankshaft rotates, the slots in the reluctor
change the magnetic field of the sensor, creating an induced voltage pulse. The longer pulse of the 58th slot identifies a specific orientation of the
crankshaft and allows the powertrain control module (PCM)/engine control module (ECM) to determine the crankshaft orientation at all times. The
PCM/ECM uses this information to generate timed ignition and injection pulses that it sends to the ignition coils and to the fuel injectors.
