What Causes the Abnormal Noise When Accelerating with AC On?
1 Answers
When accelerating with the air conditioning on, the car may produce a humming noise. The specific reasons are as follows: 1. Insufficient vehicle power: Generally, when driving at too low a speed with too high a gear, occasionally pressing the accelerator may cause a humming noise accompanied by overall vehicle vibration. This is a clear signal that the gear is too high, the transmission ratio is too small, and the engine torque is insufficient for acceleration, leading to unstable engine speed and overall vehicle vibration. If the air conditioning is on, the compressor will consume power, diverting part of the engine's output energy to the AC system, which can result in noticeable power shortage during acceleration and cause the engine to produce a humming noise. 2. Engine fan operation: Turning on the AC increases the engine load, causing the engine temperature to rise quickly. To dissipate heat from the AC system, the vehicle's cooling fan will activate. The fan's operation generates significant noise, which, combined with the engine's sound, can be heard as a humming noise in the cabin. 3. AC damage causing abnormal compressor operation: If the AC compressor is internally worn or contains foreign objects, its rotation under the belt's drive may become irregular. When the AC is on, abnormal compressor rotation can definitely cause unusual noises in the vehicle.
