Camshaft Position Sensor Replacement
What is a camshaft position sensor?
The camshaft position sensor is an electrical component that sits close to the engine's camshaft. In monitors the position of the camshaft as it rotates, and sends information about this rotation to the engine control module (ECM), the engine's computer. This information is used to control ignition timing fuel injection.
How does the camshaft position sensor work?
As the camshaft spins, the camshaft position sensor magnetically reads its position. The sensor continually sends this information to the engine's computer for comparison with data from the crankshaft position sensor.
When the two signals reach the computer, they must match. If they don't, the computer will believe that an engine timing problem is occurring, and adjust settings in order to protect the engine.
What are the symptoms related to a bad camshaft position sensor?
When the computer senses the engine is out of time, it will turn on the check engine light. The engine may stall or even just fail to start.
If the engine runs, it will run poorly and get bad fuel mileage.
Can I drive with a camshaft position sensor problem?
It's a bad idea to drive a vehicle with a failed camshaft or crankshaft position sensor — in fact, it's usually impossible.
How are camshaft position sensor issues diagnosed?
Using a scan tool, a mechanic can read where the computer believes the crankshaft and camshaft are, and compare that information to their actual position. If the reading is incorrect, the position sensor will be tested, and replaced if necessary.