How Often Should Car Drain Holes Be Cleaned?
2 Answers
It is recommended to clean car drain holes every six months. Here is some relevant information about car drain holes: 1. Air Conditioning Drain Hole: The air conditioning drain hole is usually located at the bottom of the evaporator and connected to the chassis via a hose. Its function is to drain the condensation water formed during the heat exchange process when the air conditioning is in use. This is why a puddle of water can often be seen under the car after the air conditioning has been running for a while. If the air conditioning drain hole becomes clogged, water may seep into the passenger footwell through the connection, soaking items like floor mats. 2. Engine Compartment Drain Hole: The engine compartment drain holes are typically located on both sides of the front windshield wipers, with one on each side. Since the engine compartment is a relatively open environment, dirt, leaves, and other debris can flow into it along the windshield. Engineers have designed a water deflector at the rear of the engine compartment, along the lower edge of the windshield, and incorporated drain holes in this area. Among these drain holes, the engine compartment drain hole is the most prone to clogging. Additionally, due to its proximity to the air conditioning intake, bacteria can easily breed in the hot and humid environment of the engine compartment. In severe cases, water may even flow into the car through the air conditioning intake. Furthermore, in some car models, the engine control unit (ECU) is also located in this area. If the ECU gets wet, it can cause various unexpected engine malfunctions.
Car drainage holes should be cleaned regularly. I always recommend checking them every six months, especially before the rainy season. From my experience, if the car is often parked under trees or in dusty areas, the holes can easily get clogged with leaves, mud, and debris. If not cleaned in time, rainwater can backflow into the car, soaking the carpets and, over time, causing metal parts to rust. I personally use a small air compressor to blow out the holes or poke them with a soft hose—it's very simple. Don’t forget the door drainage holes, and some cars also have holes in the trunk. The cleaning frequency depends on the driving environment; if you drive in dusty urban areas, you might need to clean them every three months. After cleaning, check if the water drains smoothly to avoid costly repairs later. The easiest way is to check them during regular car washes.
