What to Do When the Car Window Keeps Fogging Up?
3 Answers
Here are the solutions for dealing with foggy car windows: 1. Open windows for air circulation: If the fog inside the car is not too heavy, you can slightly open both side windows to create air circulation between the inside and outside of the car. This reduces the temperature difference and gradually dissipates the fog. The principle of this method is the same as using the air conditioner's cold air, but it does not increase fuel consumption. The downside of opening windows is quite obvious—it cannot be used during rain or snow, on highways, or when the fog is heavy. Additionally, opening windows lowers the temperature inside the car. 2. Use the air conditioning system: For most car owners, using the air conditioning system to defog is the most common method. Almost all cars on the market have air vents located under the front windshield. Simply adjust the air conditioning to the appropriate setting to use the airflow to remove fog. Both cold and warm air have their pros and cons. If you're in a hurry, you can use cold air as an emergency solution. However, in most cases, warm air is recommended. 3. Anti-fog products: In many markets and auto parts stores, there are stalls selling specialized anti-fog products, such as anti-fog sprays or fog-resistant towels. Spray these anti-fog products onto the inner surface of the car windows and wipe them clean. While removing dirt from the glass, they also form a thin, transparent protective film that prevents moisture from condensing on the glass and forming fog. One application can prevent fogging for about 10 to 15 days.
I've encountered fogging issues many times and have gained some experience over the years of driving. I've noticed it mainly happens when there's a big temperature difference, like when it's cold outside but warm inside the car, or when humidity is high during rainy days. My solution is: right after getting in the car, turn on the AC system using the defog mode, usually selecting external circulation with warm air, which quickly dries the windshield. If in a hurry, I slightly crack open a window for ventilation to create airflow – works instantly. Regularly clean the inside of windows as accumulated oil films make fogging worse; I often use alcohol wipes or specialized defogging cloths. Once during a foggy trip, I slightly opened the window first then stabilized with AC – worked perfectly safely. For prevention, avoid leaving wet clothes in the car or parking with windows open; good humidity control reduces issues. These tricks have proven reliable over many years of testing.
Foggy windows severely impair visibility and safety, which I take very seriously. After starting the car, I immediately turn on the defrost function with the air conditioning, selecting the hot air external circulation mode for dehumidification—this is the most effective quick solution. If the fog is too dense to see through, I first pull over and use a microfiber cloth to wipe the inside of the glass clean, avoiding the risk of driving blindly. I always keep a bottle of anti-fog spray in the car; spraying and wiping it on provides long-lasting results. Regularly checking whether the door and window seals are aging or letting in moisture is essential, and if necessary, I have a mechanic replace them. This issue can’t be taken lightly—a single oversight could lead to an accident. I always ensure clear visibility before setting off. Maintaining these habits has significantly reduced my troubles with foggy windows.
