Crankshaft Position Sensor: Description and Operation

Crankshaft Position Sensor Location:

The crankshaft position sensor is located in the passengers side of the engine block, below the exhaust manifold.

Timing Slots on Crankshaft:

The crankshaft position sensor detects slots cut into a disk in the middle of the crankshaft. There are 5 sets of slots. Each set contains 2 slots, for a total of 10 slots. Basic timing is determined by the position of the last slot in each group. Once the Powertrain Control Module (PCM) senses the last slot, it determines crankshaft position (which piston will be next at TDC) from the camshaft position sensor input. It may take the PCM up to one engine revolution to determine crankshaft position during cranking.

The PCM uses the camshaft position sensor to determine injector sequence. Once crankshaft position has been determined, the PCM begins energizing the injectors in sequence. The PCM determines ignition timing from the crankshaft timing sensor.