What Are the Causes of Car Water Leakage?
3 Answers
Car water leakage can be caused by: 1. The radiator cap is not fastened tightly; 2. Engine oil emulsification, requiring disassembly of the engine to replace the cylinder gasket; 3. Poor quality of the radiator; 4. Loose door sealing strips leading to door leakage; 5. Leakage at the rubber pipe joint—simply cut off a small section at the beginning and reinsert it. The car radiator, also known as the heat exchanger, consists of the upper tank, lower tank, radiator tubes, and cooling fins outside the tubes. Hot coolant cools down by dissipating heat to the air, while cold air warms up by absorbing the heat from the coolant. Therefore, the radiator serves as a heat exchanger.
I've driven quite a few cars and encountered leakage issues several times. The most common problems are aging windshield or door seals, especially in older vehicles where rubber components harden and crack, allowing rainwater to seep in. Another frequent issue is clogged sunroof drainage holes, where leaves or debris get stuck, preventing water from draining during heavy rain and causing leaks from the roof. Sometimes, issues with the air conditioning system can also lead to wet carpets when condensation isn't properly drained, particularly during frequent AC use in summer. Excessive water stains on the floor can not only cause mold and unpleasant odors but may also corrode metal components over time. I recommend checking these areas first – flush the sunroof drainage holes with clean water or test the door seals for tightness. If you can't fix it yourself, take it to an auto repair shop before prolonged damage occurs to the interior or electronic components. Also, try parking on level ground and avoid parking under trees where debris accumulates.
My friend's new car also had a water leakage issue, mainly around the sunroof area, where the drain tubes were either clogged or damaged. When the weather is hot and the air conditioning is used frequently, if the condensate isn't properly drained, it can leak out and wet the car's floor mats, especially under the front seats. I've also noticed that if the small drainage holes at the bottom of the doors get blocked, rainwater can accumulate and leak inside. During inspections, I can do some simple DIY fixes, like using a wire to unclog the drainage holes; if it's a problem with the sealing strips, replacing them only costs a few dollars. Don't underestimate water leakage—it can damage electrical wiring, cause short circuits, or lead to moldy carpets, making the ride uncomfortable. Regular car washes and cleaning the drainage outlets can help prevent this, but if the problem persists, it's best to seek professional repair.
