Honda Civic Water Leak Under Car: Causes & Solutions

Have you discovered water leaking beneath your Honda Civic? It is really a matter of concern if this is the case with your newly purchased Honda Civic models. Sometimes a few drops of water are okay, but if it happens regularly and in great quantity, then it can be something serious. In that case, the first question that will come to your mind is, “Why does the Honda Civic water leak under car?”

Water can leak under the Honda Civic due to a malfunction in the coolant system. The car’s cooling system includes the radiator, hose, overflow tank, heater core, etc. A crack or damage in any of the parts can lead to a water leak in your car.

However, that is only one reason why water may leak under the Honda Civic. Besides, there can be various other reasons behind the leak. If you are worried about the fluid you found under the vehicle, continue reading till the end to know why it is happening and how to fix the problem.

Is it normal for a Honda Civic to leak water underneath?

A little bit of water leaking from underneath the Honda Civic is normal if the AC is on. The water is probably coming out of the cooling system. You can ignore this.

But if the AC is turned off still, water is leaking under the car, or if a lot of water is leaking, then it is not normal. There can be various reasons why water is leaking under your Honda Civic.

The best way is to call a mechanic to inspect why the water is leaking. But first, you can take some time to investigate the cause and possibly try to resolve the problem.

Honda Civic water leak under Car: Causes & Solutions

Honda Civic Water Leak Under Car

The following are some of the probable reasons why the Honda Civic water leaked under the car and their solution:

1. Water from A/C

The most common cause of water under cars is condensation from the air conditioner. If you see that there is only a drop of water under the car and that it is coming only when you are using the A/C, then you have nothing to worry about. No solution is required, and you can ignore this water.

2. Engine coolant leak

Engine coolant links are pretty common in cars. If the water color is orange, yellow, or blue, then there is probably a coolant leak. After checking the watercolor, check the coolant level; if it is low, the coolant system is leaking.

However, the coolant system consists of various parts. You need to check the whole coolant system to know why it is leaking water. It can be because of a blown head gasket, a damaged heater core, a cracked hose, or something else. The best way to fix the leak is to find out which part is leaking and then replace it.

3. A/C malfunction

A/C malfunction

Although it is common for water to come out of the A/C, sometimes there can be problems with the A/C watering system. Then the water may leak from the hose and drop underneath the car. The problem can be with the hose, a loose pipe, or a damaged valve. You need to check the whole system and find the malfunction. Then replacing the damaged part should fix the problem.

4. A broken radiator

The radiator is another component of the car’s cooling system. If it is broken, then it can also lead to a water leak in the Honda Civic. The radiator (along with other cooling system components) is located under the hood and in front of the engine. If you see that it is broken or cracked, replacing it with a new one is the right solution.

5. Leak in the water pump

The water pump helps circulate the water through the engine’s heating and cooling systems. If there is something wrong with the water pump, such as the water getting stuck and there is a hole in the pump, then water will leak through it and drop under the car.

Besides, damage to the water pumps means the engine will overheat quickly. If you find water dripping underneath the Honda Civic and the engine is overheating, it is probably the water pump. Replace the component with a new one to avoid causing damage to the engine.

6. Transmission fluid leak

If you find reddish or orange water beneath your Honda Civic, it is probably transmission fluid leaking. The most common reason behind it is a punctured transmission pan. A leak or crack in the transmission fluid line can also cause this problem.

A transmission fluid leak can lead to serious damage to your Honda Civic’s engine. Hence, you should visit a mechanic to fix the issue as soon as possible. People tend to drive with a transmission fluid leak, which is not too dangerous but is harmful to your vehicle.

7. A damaged valve

Your Honda Civic consists of various valves connected to the combustion process and the exhaust system. These valves allow the air-fuel mixture to get into the combustion chamber and release the burned air-fuel mixture. If any of the valves are damaged, it can leak fuel underneath the Honda Civic.

It mostly happens due to bad valve seals due to improper installation or heat in the system. You can try to open and close the existing valve to see if it fixes the problem. If it still leaks fuel, then you need to replace the valves.

8. Failing brake lines

If you find a clear fluid underneath your Honda Civic that may feel slippery when you touch it, it may be brake fluid. Besides, they can also turn a yellow or brown color. It happens due to failing brake lines.

Braking fluid leaks can be dangerous as they affect the braking ability of your vehicle. Hence, you should visit a mechanic soon if you find that the braking fluid is leaking.

9. Leaking gas tank

A leak in the gasoline tank can also be the reason why there is water under your car. Gasoline is the easiest to identify due to its unique smell. They are quite expensive, and a hole in the tank can seriously hurt your economy.

If the leak on the gas tank is not too big, you can fix the issue with epoxy. Most of the time, it solves the issue, as it is unlikely to have a massive hole in the tank unless you have an accident. However, if the leak is unrepairable, you will need to replace the tank.

How to identify why water is leaking under the Honda Civic?

identify why water is leaking under the Honda Civic

Identifying the cause of leaks can be challenging. People often make mistakes and try to repair the wrong parts. But you can easily do it with a little bit of knowledge.

Also Read: Why Does My Honda Civic Beeps Multiple Times?

Here are two methods to identify why water is leaking underneath the Honda Civic:

Method 1: Paper sheet

The best and simplest way to determine the source of water leaking in a car is to use paper towels. Most of the fluids have different colors, and you can tell what fluid is leaking from your Honda Civic by watching the color.

Place a white paper sheet under your vehicle where the water is dropping. Then inspect the color to determine what fluid is leaking. 

Here is a table mentioning what color indicates what fluid:

RedTransmission Fluid or Power Steering Fluid
OrangeTransmission Fluid or Radiator Coolant
YellowRadiator Coolant
GreenAntifreeze from Water Pump, Hoses, or Radiator
BlueWindshield Wiper Fluid
Dark brownBrake Fluid or Older Engine Oil
Yellow brownNewer Engine Oil or Gear Lubricant
PinkPower Steering Fluid or Transmission Fluid

The same color fluid, on the other hand, can indicate two different fluids. For example, orange-colored fluid means transmission fluid or radiator coolant. In this situation, you should check both the transmission system and the radiator to reach a conclusion.

Method 2: Check the exhaust pipe

If you fail to identify the reason using the paper sheet, you can also check the exhaust pipe to see if any smoke is coming out. A lot of water leaking with smoke from the exhaust pipe indicates a blown gasket.

In case you are still not sure about the reason behind the leak, you can visit a service center or call a fluid inspection service.

How much does it cost to inspect a Honda Civic water leak?

It costs approximately $95 to inspect a Honda Civic for water leaks. It includes only labor costs and no costs for parts.

Once you know the reason, you can fix the issue easily. Depending on why water is leaking under your Honda Civic, the cost of repairing it can be anywhere from $100 to $500.

Also Read: Honda Civic Electric Brake Problem


1. Is the car water pump repairable?

No, a damaged water pump is not repairable. If the water pump in your vehicle is cracked or broken and leaks fluid, then you must replace the part. A water pump can cost between $200 and $400.

2. Can drive through water damage my car?

Yes. If you drive through water, there is a high probability that the water will get into the engine compartment. It can damage the engine. Besides, your car may have a short circuit, compression failure, and many other problems.

3. Can a car underwater be repaired?

Yes, if your car has been under freshwater or remained under floodwater only for a short time, then repair is possible but can be costly. However, if it has been underwater for a long time, then it is less likely to be repairable.

4. Is it OK to drive with a small coolant leak?

Yes, but only for a short time. The coolant system of a car helps the engine remain at an optimum temperature. If you drive too long with a coolant leak, the engine will overheat, leading to catastrophic results.

How expensive is it to fix a coolant leak?

It costs around $400 to $800 to fix a coolant leak (Depending on Location ). But if you ignore the leak for a long time, then it can get more expensive. It may cost more than a thousand dollars to repair the whole cooling system.