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. There are a few warning signs to watch out for before your camshaft position sensor completely fails and shuts down the engine, making replacement a necessity.
1. Vehicle does not drive like it used to
If your vehicle idles roughly, stalls frequently, has a drop in engine power, stumbles frequently, has reduced gas mileage, or accelerates slowly, these are all signs your camshaft position sensor could be failing. If you have any of these symptoms, it could mean the camshaft position sensor needs to be replaced by a professional mechanic as soon as possible. It needs to be completed before the engine cuts out and dies while you are driving, or does not start at all.
2. Check Engine Light comes on
The Check Engine Light will come on once the camshaft position sensor starts to go bad. Since this light can come on for many different reasons, it is best to have the vehicle thoroughly inspected by a professional. The mechanic will scan the ECM and see what error codes are being shown to diagnose the problem quickly. If you ignore the Check Engine Light, it can lead to serious engine problems, such as the engine failing.
3. Vehicle will not start
If the other problems are ignored, eventually the vehicle will not start. As the camshaft position sensor weakens, the signal it transmits to the vehicle’s ECM also weakens. Eventually, the signal will weaken so much the signal will switch off, and so will the engine. This can happen while the vehicle is parked, or while you are driving. The latter can be a dangerous situation.
As soon as you notice your vehicle does not drive like it used to, the Check Engine Light is on, or the vehicle will not start properly, the sensor may need to be replaced. This problem should not be ignored because eventually the engine will stop working entirely.
This article originally appeared on YourMechanic.com as Symptoms of a Bad or Failing Camshaft Position Sensor and was authored by Valerie Johnston.