What Causes Water Under the Car Carpet?

[Leilani]

Water under the car carpet is typically caused by air conditioning leaks, windshield sealant failure, or a leaking heater core. Solutions: If the carpet is only slightly wet, you can use a cleaning agent to remove dust and dirty water from the carpet. For severe water ingress, it's necessary to remove the seats and lift the floor mat for thorough cleaning. Air conditioning drain clog: If the AC drain is blocked, condensation water cannot drain properly and may leak onto the carpet. Sunroof drain clog: Blocked sunroof drains can allow rainwater to flow into the cabin. Windshield sealant failure: When the windshield sealant fails, the car's sealing performance decreases, allowing rainwater to flow along the dashboard and onto the carpet during rain. Heater core leak: If there's water leakage in the front passenger area, check if the coolant level has dropped. A decrease in coolant indicates a leaking heater core that requires immediate repair. For water accumulation under the front passenger seat, remove the foot mat and floor covering, then clean with automotive carpet cleaner. Extract standing water from the vehicle. For severe cases, open the sealing plugs at the bottom of the car chassis to drain the water. After draining, clean and disinfect the car to prevent odors and bacterial growth. Finally, open the doors to dry all wet areas. Precautions: Do not completely immerse the carpet in water for scrubbing, as this may damage the bonding between different material layers inside the carpet and prolong drying time, affecting performance and causing interior dampness. If there's water leakage in the trunk, it's usually due to improperly fitted bottom rubber plugs. For loose weatherstrips, reattach them with special adhesive to restore sealing performance and prevent water leakage. For older cars, pay attention to weatherstrip aging. When peeling occurs, reattach using a waterproof adhesive called sealant, being careful not to pull excessively to avoid damage. If part of the weatherstrip is raised or twisted (a common entry point for rainwater), replacement may be necessary when severely deformed. Door perimeter leaks are mostly caused by damaged surrounding weatherstrips - check for breaks or peeling. For small loose sections that are hard to reattach, it's better to peel them off completely before reapplying to correct twisting or looseness. After reapplying weatherstrips, apply rubber protectant to restore elasticity.