Crankshaft Position (CKP) Sensor
The CKP sensor is a magnetic transducer mounted on the engine block adjacent to a pulse wheel located on the crankshaft. By monitoring the crankshaft mounted pulse wheel, the CKP sensor is the primary sensor for ignition information to the PCM. The pulse wheel for some V6 and V8 engines have a total of 35 teeth spaced 10 degrees apart with 1 empty space for a missing tooth. The pulse wheel for some 4 cylinder engines and some V6 engines have a total of 58 teeth spaced 6 degrees apart with 2 empty spaces. By monitoring the pulse wheel, the CKP sensor signal indicates crankshaft position and speed information to the PCM. By monitoring the missing tooth, the CKP sensor is able to identify piston travel in order to synchronize the ignition system and provide a way of tracking the angular position of the crankshaft relative to a fixed reference for the CKP sensor configuration. The PCM also uses the CKP sensor signal to determine if a misfire has occurred by measuring rapid decelerations between teeth.
There are 2 types of CKP sensors used. The 2 pin variable reluctance sensor and the 3 pin Hall effect sensor.
Typical CKP Sensor