Why does the car air conditioner sometimes cool and sometimes not?

[MacLaura]

The reason why the car air conditioner sometimes cools and sometimes not is due to a lack of Freon; the filter screen is too dirty; or the air filter element is aging. The following are specific explanations: 1. Lack of Freon: The cause of this situation is usually a leak in the air conditioning system's pipeline. At this time, you can drip some water at the joint of the car's refrigerant pipeline, and bubbles will appear at the leaking spot. Once the leaking spot is found, it can be repaired. Then, go to a professional car repair shop or 4S shop to add some Freon. 2. The filter screen is too dirty: You can try to find the bypass valve on the filter element base of the filter screen. When the pressure difference between the two sides of the valve reaches a certain value, it can be opened. Generally, the oil flows into the main pipeline through this pipe. Use a car-specific lubricant to lubricate the relevant parts, and the situation will improve. 3. The air filter element is aging: If the car air filter element has been used for a long time, it may be the problem of the air filter element. This can be replaced by a professional car maintenance shop or 4S shop.