Crankshaft Position Sensor: Description and Operation

The Crankshaft Position sensor (CKP sensor) is a variable reluctance sensor triggered by a 36-minus-1 tooth trigger pulse wheel located inside the engine front cover.

The sine wave-type signal generated from the crankshaft position sensor provides two types of information:
- position of the crankshaft in 10-degree increments
- crankshaft speed (rpm)

The Powertrain Control Module (PCM) uses this information with the spark advance information to determine ignition coil turn on and turn off time.

Base ignition timing is referenced to the position of the crankshaft position sensor. It is set at 10 ± 2 degrees Before Top Dead Center (BTDC) and is not adjustable.