What are the symptoms of intake and exhaust solenoid valve failure?

[McIker]

Symptoms of damaged intake and exhaust solenoid valves include insufficient engine power during operation, severe horsepower drop, high fuel consumption, black smoke emission, and the continuous illumination of the engine warning light. Methods for handling damaged intake and exhaust solenoid valves: Typically, 4S shops will replace both the intake and exhaust camshaft solenoid valves. However, fault code diagnostics usually indicate that only the exhaust camshaft solenoid valve is faulty, so replacing both is unnecessary. After replacement, use a specialized diagnostic tool to clear the fault codes. Function of automotive solenoid valves: Automotive solenoid valves are actuators in electronic control systems, primarily serving as switching devices. They utilize electromagnetic force generated by electric current flowing through a coil to attract the valve core (overcoming spring or gravitational force), and are categorized into normally open and normally closed types. A solenoid valve is essentially an electronically controlled exhaust brake valve. The exhaust brake valve is installed between the exhaust pipe and muffler, and is used in trucks to control engine shutdown.