Camshaft Position Sensor

What Is A Camshaft Position Sensor?

The camshaft position sensor in your vehicle detects the camshaft's relative position using an electromagnet and a geared wheel, and communicates this information to the engine control module (ECM). This helps the engine computer determine which cylinder is firing in order to sync your injectors, set ignition timing, and maintain the coil firing sequence. The camshaft position sensor is a Hall Effect sensor, meaning that its internal electromagnet detects the movement of the geared wheel as it spins, and this magnet can begin to wear out or weaken over time. This may lead to inaccurate or inconsistent readings, or your camshaft position sensor may fail to send any readings to the ECM. Camshaft position sensor problems can affect a vehicle's engine timing or its ability to start at all. Rough idle, stalling, reduced power or slow acceleration, reduced gas mileage, longer start times, and a complete failure to start could all point to a failing cam sensor. A bad camshaft position sensor may also trigger the Check Engine light to alert you to a problem. If a camshaft position sensor fails completely, it may stop sending any signal at all to your engine computer, and this may cause the vehicle to stop running and fail to start again. This can be dangerous if it happens while driving, leaving you stranded, so it's best to address signs of a camshaft position failure as soon as possible. O'Reilly Auto Parts carries replacement camshaft position sensors and crankshaft sensors for most vehicles and even offers free Check Engine light testing to help you start your diagnosis and complete your repair.