Where Does the Water in the Car's Passenger Side Come From?
2 Answers
Water under the car's passenger seat usually seeps in from the sunroof. Sunroof Drain Hole Blockage: The sunroof drain hole can easily get clogged by fallen leaves and dust. Once blocked, rainwater cannot drain in time during rainfall and will seep into the car. Sunroof Rubber Seal Aging: Rubber components harden and age over time. When the sunroof rubber seal ages, its sealing performance decreases, leading to leaks during rainy days. Additionally, using a high-pressure washer or strong acidic/alkaline cleaners during sunroof maintenance can cause the rubber seal to deform or age prematurely.
Water has entered the passenger side, and I suspect it's mainly due to issues in these areas. The most common culprit is the air conditioning system, as there's an AC drain pipe under the passenger seat. If it gets clogged with dust or leaves, condensation water can seep into the carpet. Another possibility is aged or deformed door seals, allowing rainwater or car wash water to leak through the door gaps. A clogged or cracked sunroof drain pipe can also direct water to the passenger side. Poor sealing of the windshield gasket is another potential cause, especially during rain or car washes. Additionally, blocked drainage holes under the body floor can cause water to backflow. If you notice this issue, it's best to inspect these areas. I personally make a habit of cleaning the drain pipes regularly to prevent mold and electrical short circuits. If the problem is severe, it's advisable to visit a repair shop promptly to avoid long-term damage.
