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.
How is a camshaft position sensor replaced?
Replacement of the camshaft position sensor is completed by disconnecting the electrical connector or connectors and unscrewing the sensor. If required, sealant will be applied before inserting the new sensor into the engine. Finally the electrical connector is connected, and the vehicle is tested to confirm the repair.
There are two common locations for the camshaft position sensor: inside the timing cover and near or on the engine's valve cover.
RepairPal recommendations for camshaft position sensor issues
When replacing the camshaft position sensor, make sure there are no obvious oil or coolant leaks that could ruin the new sensor.
High-quality sensors — preferably OEM parts — should be used, as lesser products will likely lead to a repeated repair. Also, the vehicle's timing belt should be inspected at this time. If the timing belt or timing chain has failed, it will need to be replaced.
Can I replace the camshaft position sensor myself?
Diagnosis is key when it comes to sensor replacement, as other problems could cause the same symptoms. If the issue can't be diagnosed at home, a professional technician should be trusted with the issue.