Why is There Water Dripping From My Car?

Any time you see a puddle of liquid under your car, your immediate thought is usually something bad like oil, coolant, or transmission fluid. While it’s always important to investigate any leaks coming from your vehicle, a puddle of water is not a cause for concern. In this article, we are going to look at the causes of water dripping from under your vehicle, and why it’s a harmless byproduct of normal engine operation. 

Where Does The Water Under My Car Come From?

When you think about the common fluids in a car, water is not one of them. Oil, windshield washer fluid, coolant, transmission fluid, and brake fluid, but not water. When a puddle of water forms under your car, it’s not coming from inside any of the systems in your vehicle, it’s a result of condensation. 

What is Condensation? 

Condensation is when matter changes from a gas state to a liquid state. You may remember this concept from science class, and see it throughout your day-to-day life (think about a cold water bottle in the hot sun “sweating”). This process is what causes water to drip under your vehicle in nearly all cases. 

Condensation From the A/C

The primary cause of water dripping under your car is condensation, but the system causing it is more often than not the air conditioning. The A/C system uses the same property of condensation in addition to the reverse process, evaporation, to cool the air coming through the vents. While all of these phase changes are happening within the A/C system, the lines that route the refrigerant become very cold. Since the air conditioning is normally run when it’s very hot outside, these lines will “sweat”, just like a water bottle does. 

Climate control dials on interior of car

Condensation from the Exhaust

Another common cause of water dripping from your car is from the exhaust system. The same principles apply here, but you are more likely to notice water dripping from your tailpipe when it’s cold outside. The difference in temperature between the outside air and the hot exhaust piping causes water vapor to condense, and eventually leak out of the tailpipe.

Close-up of dual tailpipes on rear of vehicle

Is it Water or Another Fluid?

Even though water drips are harmless and common, it can still cause anxiety to see any fluid puddling up under your car. Luckily, it isn’t hard to figure out what the fluid is. All you have to do is get a paper towel and soak up some of the liquid. If the towel turns dark black or brown, pink, blue, or red, it’s likely you have an actual fluid leak. In this case, you should get your car to a trusted mechanic as soon as possible to prevent further issues from occurring as a result of the leak. 

Auto Repair Service in Carlsbad

Even if the puddle under your car is just water from condensation, you still need to keep your vehicle well-maintained to prevent a legitimate fluid leak. Call or schedule an appointment at Carlsbad Auto Service today and let our team of expert technicians keep your car running as it should.

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