What causes the wiper to not clean the car glass properly in the rain?
4 Answers
The reasons why the wiper does not clean the car glass properly are as follows: 1. Wiper angle: The angle of the wiper may cause it to not clean properly, and it can be resolved by adjusting it. If the downward pressure of the wiper is too strong, it may lead to uneven force distribution, in which case the distance between the springs needs to be loosened. 2. Foreign objects on the wiper: If you hear a "squeaking" noise when the wiper is operating, it is likely due to foreign objects trapped between the wiper blade and the windshield, which can also prevent the wiper from cleaning properly. In this case, check for any foreign objects and remove them if present. Alternatively, the wiper blade may be too rough, and smoothing it with sandpaper can help. 3. Wiper hardening: Everything has its lifespan, especially for vehicles frequently parked outdoors, which are inevitably exposed to sun and rain. Over time, this will accelerate the aging of the wiper rubber, reducing its effectiveness. In such cases, it is necessary to replace the wiper as soon as possible.
I always encounter oily stains on the windshield during long-distance drives, which make it impossible to wipe clean when it rains—so dangerous. This is usually caused by oil contamination on the glass surface, such as tree sap buildup when parked under trees or roadside smoke and grease deposits. The oily layer causes rainwater to bead up instead of spreading evenly, and the wiper blades bounce off, leaving the view unclear. Another possibility is that the wiper blades themselves are worn out or dirty, with deformed rubber unable to press down the oil layer. I once almost got into an accident because of this—I immediately pulled over, first wiping the glass with a damp cloth, but when that didn’t work well, I went straight to a car wash for professional cleaning. I recommend checking the windshield after each parking session, using glass cleaner for regular maintenance, keeping the wiper blades clean or replacing them in time. This can reduce blurring risks and ensure driving safety, especially on rainy days—don’t overlook this. Dash cams often record similar accidents.
When car windshields don't wipe clean during rain, surface grease is often the culprit. Substances like oil or tree sap create a hydrophobic layer, preventing rainwater from sliding off evenly and instead forming droplets that roll around when the wipers push them, impairing visibility. Other causes include poor parking conditions, such as accumulating kitchen fumes near restaurants, or worn and deformed wiper blades that can't press firmly against the glass. The solution is simple: first try wiping the glass with a mixture of household baking soda and water to remove grease. If that doesn't work, visit an auto repair shop to replace the wiper blades. When washing your car, remember to clean the dust and grime on the inside of the glass—both sides need attention for optimal performance. Having repaired many cars, I've found that stubborn grease requires professional glass cleaner sprays; avoid using tap water as it can make the surface stickier. Regular maintenance saves hassle and extends the windshield's lifespan.
My car's windshield wipers don't clean properly when it rains, leaving a blurry film like an oily residue. The main reason is oil contamination on the glass that hasn't been removed, such as tree resin from parking near trees or oily particles in airborne dust. Rainwater can't wash it away and instead worsens visibility. Simply put, the wipers might be worn out—the rubber blades could be deformed and unable to press firmly against the stains, or the glass may have accumulated grime over time from lack of cleaning. I make it a habit to regularly spray a mixture of vinegar and water, wiping it a few times to easily remove the oily layer, while also checking the wiper blades for cracks and replacing them if needed. Safety is crucial—poor visibility in rainy conditions can easily lead to accidents. I immediately slow down and turn on the fog lights to ensure it doesn't affect my journey.
