The camshaft position sensor gathers information about the vehicle's camshaft speed and sends it to the vehicle's engine control module (ECM). The ECM uses this data to determine the timing of the ignition, as well as the timing of the fuel injection that the engine requires. Without this information, the engine would not be able to function properly. Over time, the camshaft position sensor can fail, or become worn down, due to accidents or normal wear and tear.