Camshaft Position (CMP) Sensor

CMP sensor is a Hall Effect sensor located in the engine front cover. CMP sensor produces 4 pulses for every 2 revolutions of the engine (one pulse is slightly longer than the others). CMP sensor signals are generated from 4 gaps on cam gear (one gap is smaller than the others). CMP sensor signals are used by ECM to correct fuel injector timing for fully sequential operation and for active knock control.

If CMP sensor fails, default strategy is to continue normal ignition timing. Fuel injectors will be actuated sequentially based on top dead center timing. Injection timing will either be correct or one revolution out of synchronization. A fault is indicated by illumination of the MIL.