
Water can enter a car through the sunroof, doors, or chassis. Here are the details: 1. Vehicle chassis: The chassis typically has drainage holes designed to expel water after wading. If these holes get clogged with debris or their rubber seals deteriorate/detach, water infiltration becomes likely. 2. Precautions: Never attempt to restart the engine immediately after hydro-lock occurs. Since the exact cause of stalling can't be instantly determined, reckless ignition attempts may inflict unpredictable severe damage to the vehicle.

I remember my car also got flooded during last year's rainy season. When I took it to a mechanic for inspection, we found the main leak was from the sunroof drainage tube. The rubber had aged, causing cracks at the connection points, allowing rainwater to flow down the A-pillar and under the floor mats. Another critical issue was the deformed door seals, especially near the passenger door frame where accumulated leaves blocked the drainage holes. The most surprising leak point was the AC air intake - the plastic cover panel under the windshield had cracked, letting rainwater pour directly into the blower during heavy storms. I recommend cleaning the sunroof tracks during every car wash and regularly checking if door seals have hardened. Personally, I now test the seals quarterly by spraying water with a hose, since dealing with moldy carpets is such a hassle to repair.

As an experienced driver, I've encountered water leakage issues several times, and found that leaks mainly occur at body seams. When the windshield edge seals age, they allow water seepage that flows along the dashboard frame to the driver's seat. Also, the wiring grommets in the chassis can leak if loosened during maintenance. Trunk water ingress is usually caused by failed sealant around taillight mounting holes. Reminder to all car owners: after heavy rains, remember to check for water accumulation in the spare tire well - it's the lowest point and most prone to pooling. Keep the drainage holes under door sill trims clear, otherwise they may rust through the floor panels.

Last week, while handling a customer's vehicle water ingress case, it was discovered that the culprit of the leak was a clogged sunroof guide rail. Long-term accumulation of sludge caused rainwater to backflow into the headliner, soaking the entire roof lining. The cracking of the rubber sleeves at the window regulator wire pass-through is also a high-risk area, especially in older vehicles, where water leaks directly into the door trim panel along the wiring harness. The aging of the sealing ring at the air filter intake is equally hazardous. If the sealing of the rear ventilation flap is not tight, water jets from car washing can seep back in.


