What Causes the Front Windshield of a Car to Be Unclear?

[ErinAnn]

When there is a temperature difference between the inside and outside of the car, the windshield may fog up. Turning on the air conditioning and switching to the defog mode can help. Here are some methods to prevent fogging: Proper Use of Windshield Washer Fluid: Drivers can effectively use windshield washer fluid to address the issue of blurred vision while driving. During regular windshield maintenance, it's important to choose the appropriate washer fluid based on the season and weather conditions. This will make cleaning much more effective and keep the windshield clearer. Applying Window Tint Film: Another option for car owners is to apply window tint film to effectively protect the car's windshield.

[Jesse]

I've been driving for over a decade and often encounter issues with blurry windshields. The most common problem is the oil film on the outside of the glass, caused by oil and dirt splashed from trucks mixed with bug residue and tree sap. Over time, it creates a hazy layer, making it impossible to clear even with wipers during rain. Another issue is aging or deformed wiper blades, which leave water streaks and severely affect visibility—usually requiring replacement every two years. Winter fogging is the most annoying, where exhaled warm air inside the car condenses on the cold glass. The most effective solution is to turn on the AC and blow cold air at the windshield; the fog clears in minutes. When washing the car, remember to clean the inside of the glass—fingerprints and grease buildup can cause glare. In heavy rain, if the wipers fail, don’t force it—pull over or drive slowly to a repair shop. Regular windshield maintenance is crucial—safety first.

[LilaRose]

Living in the southern coastal area, I've gained plenty of experience with windshield issues. During the rainy season, the glass always gets covered in condensation. At this point, I have to turn on the air conditioning's defogging function in advance, setting the airflow to maximum and directing it at the windshield. Wiper blades deteriorate especially quickly by the seaside—humidity combined with intense sun exposure causes the rubber to harden and crack, resulting in squeaky wipes and water streaks left behind. Every week, I clean the glass with a dedicated glass cleaner, paying extra attention to removing oil films; otherwise, when it rains, the glare from oncoming headlights becomes unbearable. Once, bird droppings on the glass weren't cleaned promptly and left permanent marks after drying—I regretted it so much. Now, I always avoid parking under trees, and in summer, I'm extra cautious about tree resin drips, which can only be removed with alcohol wipes.

[BrookeDella]

When I first started driving, I was always troubled by the windshield. In the mornings, the inside of the glass would be completely fogged up, and I would fumble around looking for the air conditioning button. Later, I learned that I could simply press the front defrost button. The first time I encountered oil film, the headlights at night scattered like fireworks, and I thought my vision was blurring. It turned out the car wash guy said it was due to oil refraction. Now, I've learned to regularly replace the frameless wiper blades, which fit better than the standard ones. Before the rainy season, I check if the rubber strips have any cracks. In the summer, I try to park in the shade as much as possible, as the sun's exposure can deform the rubber of the wiper blades. For the inside of the windshield, I use a soft cloth dipped in neutral cleaning solution to wipe it, avoiding any water stains.