Crankshaft Position Sensor

Crankshaft position sensor, used on 3.8L, utilizes a Hall Effect switch mounted near vibration damper. Sensor monitors vibration damper position (crankshaft position) and sends signals to ignition control module. These signals provide PCM with a TDC position reference for each piston, as well as supplying an engine speed (RPM) signal.

The 3.1L and 3.4L Direct Ignition System (DIS) crankshaft position sensor protrudes through side of engine block to within .05" (1.3 mm) of an internally-mounted crankshaft reluctor ring. The reluctor ring is a special trigger wheel cast into the crankshaft. As crankshaft rotates, notches in reluctor ring change the magnetic field at the tip of the position sensor. This creates an induced AC voltage signal in the sensor windings, resulting in reference signals which are sent to PCM by ignition control module. This allows PCM to compute crankshaft position and RPM and fire appropriate ignition coil at the proper time.