Hey, Why is My Car Leaking Water?
Is Your Car Leaking Water?
The water leak is caused by condensation in the air conditioning system. In this case, don’t sweat; the leak is actually a designed condensation release as long as it is not leaking into the passenger compartment. However, there could also be serious reasons, like a window washer tube leak, damaged windshield, window or door seals, or sunroof leak.
If you see a puddle under your vehicle, check if it's a vital fluid, like coolant or engine oil. Sometimes, it may just be water. While leaking water usually isn't as catastrophic, water leaks can damage your vehicle.
Water leaking into your vehicle is likely to develop problems. Aside from damage to your headliner and carpet, water can disrupt and interfere with the car's electrical system, causing a short circuit. Moist environments also present the danger of mold or mildew inhalation.
Keeping your vehicle's interior dry and sealed is the key to preventing water damage. Unfortunately, finding the source of the leak isn't always easy and sometimes requires a technical solution.
Let's Get To The Bottom Of It!
- Q: Is there a puddle of water under your vehicle near the footwell after driving on a hot day with the AC on?
You may also smell a musty odor inside the vehicle, or the carpet on the passenger side may get wet.
The air conditioning freezes moisture in the air and condenses them on the evaporator core (where hot air is exchanged for cool air). This condensation drains into a catch pan attached to a drain hose. This hose is meant to discard the water under the vehicle. This is a normal part of a vehicle's functioning air conditioning process.
You may also hear a sloshing noise under the dash or feel cold water dripping on your feet while driving.
During the air conditioning, moisture in the air freezes and condenses on the evaporator core (where hot air is exchanged for cool air). This condensation drains into a catch pan attached to a drain hose. This hose is meant to discard the water under the vehicle, but if it's clogged, the condensation will accumulate in the catch pan until it overflows. This water winds up soaking the carpet on the car's passenger side without proper drainage.
You may hear a whistling noise while driving or find the trunk's carpets wet.
A vehicle's sunroof has a weatherproof seal between the glass and the roof. Since this seal is made from rubber, it degrades over time and with exposure to weather. If it gets brittle or torn, water can leak onto the headliner (the vehicle's ceiling liner), causing visible stains.
You may hear a whistling noise while driving or smell a musty odor from the vehicle.
Modern vehicles use a high-strength adhesive to bind the windshield's glass to the frame. The seal will be breached if this binding material becomes stiff and cracks. This allows water to seep in during wet conditions, causing you to see droplets of moisture on the dash.
You may also have intermittent electrical issues or find the carpet in the back seat is wet.
There is a continuous weather strip that forms an airtight seal around the doors of the vehicle. However, since the weather strip is made of rubber, it degrades and gets hard over time. As a result, opening and closing the car doors wear on it as well. Plus, if the weather strips no longer form an airtight seal, wind leaks in when you drive, creating a whistling noise as it blows through the breaches in the seal.
You may also find puddles of water under the vehicle near the floorboard or under the middle or back of the car.
The front windshield washer system comprises a reservoir, hoses, and spray nozzles. Unfortunately, any of these components can get damaged with age, wear, or exposure to weather. If this happens, they become brittle and crack, leading to leaks. These leaks allow blue windshield washer fluid to spill out and become puddles underneath the vehicle.
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Vehicle Health Inspection Proof
Explore the following typical inspection results that show a potential cause for the symptom and select the one you believe is similar to your vehicle's issue.
- Condensation from air conditioner
- Drain in air box plugged
- Sunroof leaking
- Windshield leaking
- Doors leaking
- Leaking window washer
The proof image shows condensed water coming from the air box drain tube during normal air conditioning operations.
A customer dropped off their vehicle upon noticing a puddle of clear liquid underneath it when parked. They thought something was wrong with the cooling system, causing antifreeze to leak onto the ground.
The technician noticed nothing about the customer's concerns on the test drive or the vehicle health inspection.
The mechanic raised the vehicle onto the lift and noticed water on the ground. They traced the water up to the drain hose of the evaporator air box drain. The technician informed the customer that this was normal behavior for this vehicle.
So, the water wasn't leaking because of a faulty part or damaged seal; the droplets were expected per the vehicle's build. In summary, water expelled by air conditioners through the car's underside is ordinary.
1/6Typical Fixes to Address the Cause(s)
The following chapters bases themselves on experiences from our auto repair shop; we'll describe related problems' causes and fixes.
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Vehicle Symptoms
Below are just a few examples of typical Symptoms and Fixes your car might be experiencing
Other things your auto repair shop might talk about:
Coolant leaking. Coolant leak. Warm air. Notice water dripping. Rubber seals. Vast majority. Windows open.