What Causes the Engine Fan Noise to Increase?
2 Answers
Engine fan noise increases due to: 1. Abnormal wear of the timing chain; 2. Improper engine valve clearance; 3. Malfunctioning engine turbocharger; 4. Poor sealing of the engine intake manifold and ducts; 5. Poor sealing of the exhaust manifold; 6. Abnormal internal wear of the engine. The fan is controlled by the engine coolant temperature switch and is categorized into silicone oil clutch cooling fans and electromagnetic clutch cooling fans. The engine fan is installed behind the radiator and draws air from the front of the radiator when activated. The fan starts and stops automatically based on the coolant temperature. Its operational requirements include: 1. High current during fan motor operation, necessitating high-quality wiring; 2. High-speed rotation during operation, requiring advanced manufacturing processes.
I noticed the fan noise has increased, mainly because the fan itself might be having issues. For example, the fan blades could be worn or deformed—over time, the edges wear down, causing extra noise during rotation. It could also be a bad bearing; that thing spins inside the bearing hole, and when it wears out, it produces a buzzing sound. Sometimes, the cooling system isn’t performing well, causing the engine temperature to rise and the fan to run at high speed, naturally making the noise louder. Like one time, I encountered a car with a faulty temperature sensor, and the fan kept running wildly. I recommend first checking the fan assembly for any leaves or debris stuck in it and cleaning it out. If the noise persists, you should also check if the belt is loose to avoid potential hazards. Timely maintenance in these areas is crucial—don’t wait until the fan completely fails to fix it, as driving with that uncertainty isn’t reassuring.
