Why is the door drain hole sealed with tape?
2 Answers
To prevent water or foreign objects from entering through the drain hole during transportation. Below is relevant information about door drain holes: 1. Concept: Vehicle drain holes are outlets designed to drain accumulated water from the vehicle during rainy weather. Generally, vehicle drain holes are located in the following areas: the front windshield area of the engine compartment, the four corners inside the sunroof, the lower part of the front and rear doors, inside the fuel tank cap, at the bottom of the spare tire in the trunk, and the gaps between the front and rear headlights and the fenders. 2. Precautions: There is usually a drain hole below the fuel tank cap. If it becomes blocked, water may accumulate in the fuel tank during car washes or rainy weather, potentially damaging the fuel tank. The spare tire in the trunk is generally located in a lower part of the vehicle body. When driving through water, if the water level rises above the headlights, water may seep in and reach the interior. The drain holes in this area are used less frequently.
As a veteran driver with 15 years of experience, I once mistakenly used tape to cover the drainage holes thinking it would reduce wind noise. However, after heavy rain, the doors started squeaking when opened and closed. Upon removing the door panel, I found serious water accumulation and rust inside. The mechanic explained that the drainage holes serve a simple purpose—to allow rainwater that seeps in to flow out. Never block them, or else water will corrode metal components and wire connectors inside the door cavity. Severe rust can damage the power window mechanism and even cause leaks into the car, affecting electrical safety. Now, I regularly use thin wire to clear out mud and leaves from the holes and advise friends to check the drainage holes after washing their cars in rainy weather to keep them unobstructed. Blocking them with tape or debris will only accelerate damage to the car.