What are the symptoms of a camshaft sensor failure?

　　Unstable starting and running: A sensor failure prevents the ECU from detecting changes in the camshaft position, resulting in difficult ignition, delayed start-up, possible sudden stalling when the engine is warm, and abnormal vehicle vibration at idle.

　　Degraded acceleration performance: The intake and exhaust systems fail to function properly, resulting in weak acceleration during driving, sluggish throttle response, and a noticeable loss of power when overtaking at high speeds; some models even automatically limit the maximum engine speed.

　　Increased fuel consumption: A malfunctioning electronic fuel system leads to erratic fuel injection, resulting in incomplete combustion that can increase fuel consumption by 15%–30%. Visible black carbon deposits or black smoke may also be observed in the exhaust pipe.

　　Fault indicator light on: The engine fault light on the instrument panel remains steadily illuminated or flashes, and the OBD system typically stores diagnostic trouble codes such as P0340 for circuit or performance faults, requiring a detailed inspection.