Can a Car Be Washed After Being Exposed to the Sun for a Day?
4 Answers
A car that has been exposed to the sun for a day should not be washed directly. The reasons are as follows: 1. Harmful gases can be produced: Once a car is exposed to the sun, a large amount of harmful gases will be released inside the car, as the interior is mostly wrapped in plastic and leather. Therefore, under high temperatures, harmful gases such as formaldehyde can easily be produced. 2. Brake disc cracking: In hot summer, if a car is washed with cold water after being exposed to the sun for a long time or after a long-distance trip, the brake disc may crack. 3. Paint cracking: If the car is washed immediately after being exposed to the sun, the paint may crack within two or three years, and in severe cases, bubbles may appear.
Recently, someone asked about this, and I think it's best not to wash the car immediately after it's been sitting in the sun all day. The body temperature can reach 60-80 degrees Celsius, and the paint and glass expand when heated. Sudden contact with cold water causes rapid contraction, known as thermal shock, which may lead to paint cracking, glass fractures, or aging of window seals. I've seen customers replace their glass after such an operation, wasting thousands of dollars. It's recommended to move the car to a shaded area and wait 20-30 minutes for the temperature to drop before washing. If in a hurry, use lukewarm water instead of ice-cold water. It's best to wash the car during the cooler hours of early morning or evening, and park under shade or in a garage to minimize such issues. A car wash machine with temperature control is even better. Protecting the car's paint can extend its lifespan and save unnecessary repairs. To cool down the car body, you can use a damp cloth to wipe the surface for faster heat dissipation, but avoid using large amounts of water.
Speaking of this topic, I learned a lesson myself. One summer afternoon, my car was parked under the sun, and I directly sprayed it with a water gun, resulting in a small crack on the windshield. The mechanic told me that a hot car body encountering cold water is like pouring oil into a hot pan, creating stress that damages the glass, especially for older cars which are more fragile. Since then, I've developed a habit: after the car gets hot, I first park it in the shade to let it cool down, or use a spray bottle with warm water to ease the temperature difference. Don't wash the car too frequently; once a week is enough, and be extra careful about the water temperature in hot weather. In daily maintenance, regular waxing can help buffer the impact of thermal shock, and the windows will also fog up less. Safety comes first for drivers, as glass issues affecting visibility can be very dangerous.
Although modern car materials have improved, there is still a risk of micro-damage to the paint or glass fragility when washing the car with cold water immediately after exposure to hot sun. I recommend waiting for the car body to cool naturally or using lukewarm water to reduce thermal shock. Before washing, touch the roof of the car – if it's very hot, wait a while; it's simple and safe. Additionally, choose early morning or evening for summer car washes when the air is cooler and more comfortable. Parking in shaded areas can prevent excessive heat buildup.
