Does it matter if it rains with the car window slightly open?
4 Answers
Leaving a small gap in the car window during rain is generally not a problem if only a little water gets in; however, if a significant amount of water enters, it can potentially cause electrical short circuits. Here are some safe ways to use car windows: 1. Opening a single window: To dissipate odors (like smoke): The main purpose of opening a single window is to remove unpleasant air from the car. When smoking, opening a side window allows the secondhand smoke to exit quickly. While some smoke might escape elsewhere, this method is the most effective. Cracking the window slightly helps dissipate fog faster without blowing air onto passengers in the back. 2. Closing the front window on one side (quick odor removal): This means closing the window next to the driver and opening the other three windows. This creates an unbalanced airflow with a clear directional flow, allowing odors inside the car to be expelled quickly. 3. Never open windows on the same side while driving at high speeds (dangerous): When driving on the highway, either keep all windows closed or open just one window. Avoid opening two windows on the same side simultaneously, as this can cause strong airflow to rush into the car from one side.
As a veteran driver with over 20 years of experience, I can confirm that leaving car windows slightly open on rainy days is indeed troublesome. Rainwater can slowly seep into the car, dripping onto seats or carpets, which when soaked can easily lead to mold and unpleasant odors, costing hundreds to repair. Even worse, water droplets entering window switches or electrical circuits may cause short circuits, potentially affecting driving safety. I once saw a neighbor's car fail to start due to this minor oversight of not closing windows promptly, requiring significant effort to fix. It's best to develop the habit of closing windows tightly while driving or temporarily sealing gaps with tape after parking. If the rain is heavy, turning on the air conditioning for dehumidification can provide temporary relief, but prolonged exposure will lead to significant vehicle damage.
I usually pay great attention to car maintenance, and leaving windows slightly open during rain is no trivial matter. Rainwater can seep into the door interior through the gaps, gradually corroding metal components like window regulators and lock mechanisms, which are expensive to repair. It might also drip onto electronic control units, causing short circuits and fault warnings. I learned this the hard way when I forgot to close a window during rain—the next day, the car interior was full of moisture, taking half a day to clean up. My advice is to double-check all windows after parking or install rain guards for long-term protection, ensuring ventilation without water ingress. If driving in the rain, using the AC’s external circulation mode can reduce humidity intrusion, keeping the cabin dry and minimizing wear risks.
As a daily commuter who drives every day, leaving the car window slightly open on rainy days is definitely not a good idea. Rainwater can seep in and wet the seats, making your backside feel chilly and uncomfortable while driving. If the wind picks up, more raindrops can splash inside, potentially causing stains or rust on the interior, which looks unsightly. I usually make sure to close all the windows before it rains to avoid rushing at the last minute. Nowadays, many new cars come with a remote window-closing feature—just a tap on your phone, and it's done, which is quite convenient. If you really want some air circulation, you can use the car's ventilation vents instead of leaving the windows open and giving rainwater an easy entry.
