Why is the car still dripping water after turning off the engine?
3 Answers
There are several reasons why a car may drip water after the engine is turned off: 1. Drainage from the body drainage holes to prevent water accumulation: The car chassis is equipped with specially designed drainage holes to discharge accumulated water from the vehicle body during rainy or snowy weather. 2. Air conditioning system drainage: It is normal for the air conditioning system to drain water during summer. Due to the high temperature inside the car, the cooling system is activated to lower the interior temperature. After turning on the air conditioning, the compressor located in the engine compartment (low-pressure area) will also condense moisture from the air, causing it to drip onto the ground. The low-pressure pipes of the car air conditioning system are not wrapped with thermal insulation foam, making the pipe surfaces prone to condensing moisture from the air. Water droplets will then gather and drip from the lowest point of the pipes.
Last week when I washed my car, I also noticed water dripping after the engine was turned off. This is actually completely normal. The most common reason is the accumulated condensation water from the air conditioning system's drain pipe, which slowly drains after shutdown. Another common location is near the exhaust pipe, where water vapor condenses from engine combustion. I remember last summer when I was on a long drive, a puddle formed under the car after stopping at a service area. I was worried about fluid leakage at the time, but later learned that burning one liter of gasoline can produce nearly one liter of water! As long as it's clear water and not oil, and the dripping is from the middle or rear underside of the car, there's no need to worry. On the contrary, if the air conditioning drain pipe gets blocked by leaves, it may cause backflow, which is when cleaning is needed.
As a driver who frequently takes long-distance trips, I've noticed that every car drips water after being turned off, especially after using the air conditioning in summer. The principle is simple: when the air conditioner's evaporator absorbs heat, it generates a large amount of condensation, much like the water droplets on the outside of a chilled beverage bottle. After turning off the engine, this water drips out through a dedicated drainage pipe. Water dripping from the exhaust pipe is even more noticeable because the water vapor in the exhaust gas instantly liquefies when it meets the cold walls of the exhaust pipe. Once, after driving in sub-zero temperatures and turning off the engine, I even saw icicles forming on the exhaust pipe. As long as the water is clear and odorless, there's no need for concern. Instead, one should be wary of leaks under the engine, which could indicate coolant leakage. After turning off the engine, observe for about ten minutes—normal dripping will stop quickly.
