Camshaft Position (CMP) Sensor
A 3-pin Hall Effect type sensor or a 2-pin variable reluctance CMP sensor is used. CMP sensor is used to determine camshaft position and to identify when piston No. 1 is at TDC of compression stroke. CMP sensor signal is used by PCM for synchronizing firing of sequential fuel injectors. Applications with Coil On Plug (COP) ignition also use CMP signal to select the proper ignition coil to fire.