LaCrosse V6-3.6L VIN 7 (2006)
Crankshaft Position Sensor: Description and Operation
CRANKSHAFT POSITION (CKP) SENSOR
The crankshaft position (CKP) sensor works in conjunction with a 58 tooth reluctor wheel on the crankshaft. The engine control module (ECM) monitors
the voltage between the CKP sensor signal circuits. As each reluctor wheel tooth rotates past the sensor, the sensor creates an analog signal. This analog
signal is processed by the ECM. The reluctor wheel teeth are 6 degrees apart. Having only 58 teeth leaves a 12 degree span that is uncut. This creates a
signature pattern that enables the ECM to determine the CKP. The ECM can determine which pair of cylinders is approaching top dead center based on
the CKP signal alone. The camshaft position (CMP) sensor signals are used in order to determine which of these 2 cylinders is on a firing stroke, and
which is on the exhaust stroke. The ECM uses this to properly synchronize the ignition system, the fuel injectors, and the knock control. This sensor is
also used in order to detect misfire.
