The reasons why the air conditioning is particularly loud when turned on in a car are: 1. Dirty or stuck throttle valve: When the air conditioning is turned on, the compressor also starts working, and since the compressor is driven by the engine, turning on the air conditioning increases the engine's load. This means the engine needs to increase the throttle opening to allow more air intake. When the throttle valve has carbon deposits or is stuck, it can cause engine vibration and abnormal noise, which becomes more noticeable after the air conditioning is turned on. 2. Abnormal noise from the air conditioning pump: There are two main reasons for abnormal noise from the air conditioning pump: the electromagnetic clutch and the bearings inside the air conditioning pump. The noise from the electromagnetic clutch is mainly caused by wear, leading to increased gaps, while the noise from the air conditioning pump bearings is primarily due to a lack of lubricating oil. If these issues are not resolved promptly, they can lead to the burning out of the air conditioning pump, rendering it unable to perform cooling work. 3. Improper tension of the compressor drive belt: If the drive belt is too loose, the electromagnetic clutch is prone to slipping; if the drive belt is too tight, the load on the electromagnetic clutch increases. Improper tension of the drive belt can cause abnormal noise in mild cases and damage the air conditioning compressor in severe cases.
