What Are the Symptoms of a Faulty Camshaft Sensor?
2 Answers
The manifestations of a faulty camshaft sensor include difficulty in ignition, hard starting, unstable idle, inability to accelerate, weak engine performance, increased fuel consumption, vehicle shaking, persistent illumination of the malfunction indicator light, sudden engine shutdown when the car is hot, jerky driving, and accelerated engine wear. Below is an introduction to the camshaft position sensor: 1. Working Principle: The camshaft position sensor is the main control signal for ignition. When the sensor shaft rotates with the crankshaft and the camshaft, the light-transmitting holes and opaque sections on the signal disk pass between the LED and the phototransistor. The light emitted by the LED is alternately blocked and transmitted by the signal disk, thereby alternately illuminating the phototransistor of the signal generator. This generates pulse signals corresponding to the crankshaft and camshaft positions in the signal sensor. 2. Function: The camshaft position sensor collects the position signal of the camshaft and inputs it into the ECU, enabling the ECU to identify the top dead center of the cylinder compression for sequential fuel injection control, ignition timing control, and knock control. Additionally, the camshaft position signal is used to identify the first ignition timing during engine startup.
When the camshaft sensor fails, the car becomes particularly difficult to start, often requiring multiple attempts to ignite. Acceleration becomes as slow as a snail's pace, with no response when pressing the throttle. The engine may also suddenly jerk, making the whole car vibrate, especially when going uphill or at high speeds. The check engine light usually comes on, acting like an alarm. I remember my old car had this issue—fuel consumption skyrocketed because the sensor couldn't control the ignition timing, causing the fuel injection to go haywire. If not repaired promptly, it could lead to stalling or even engine seizure, and in severe cases, you might end up spending a fortune on an engine replacement. It's advisable to first check the OBD fault codes to confirm the issue, avoid DIY fixes, and take it to a professional repair shop as soon as possible.
