The Crank Position sensor (CKPS) 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 Crank Position sensor (CKPS) is the primary sensor for ignition information to the PCM. By monitoring the pulse wheel, the Crank Position sensor (CKPS) signal indicates crankshaft position and speed information to the PCM. By monitoring the missing tooth, the Crank Position sensor (CKPS) 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 Crank Position sensor (CKPS) configuration. The PCM also uses the Crank Position sensor (CKPS) signal to determine if a misfire has occurred by measuring rapid decelerations between teeth.

The Camshaft Position sensor (CMPS) detects the position of the camshaft. The Camshaft Position sensor (CMPS) identifies when piston number 1 is on its compression stroke. A signal is then sent to the PCM and used for synchronizing the sequential firing of the fuel injectors. Coil on plug ignition applications use the Camshaft Position sensor (CMPS) signal to select the correct ignition coil to fire. Inline engines with 2 camshafts and with CVVT(Continuously Variable Valve Timing) are equipped with 2 CMPSs. The second sensor identifies the exhaust camshaft position.