Why Is There Water Coming Out of My Exhaust?

Not sure whether the water dripping from your tailpipe is a cause for concern? We’ve got all the info on what’s normal and what’s not.
Written by Natalie Todoroff
Reviewed by Melanie Reiff
background
Water condensation in your car’s engine, an overheating engine, your catalytic converter, a blown gasket head, and faulty pistons could all be potential causes of water coming out of your exhaust pipe. While some of these indicate that the internal combustion process is working as it should, others can indicate a bigger problem.
While operating, your engine creates all kinds of fume and liquid byproducts that need to be expelled through the tailpipe. Sometimes, some of this byproduct includes water. A small amount of water isn’t necessarily a cause for concern, but it can occasionally indicate a serious problem. But, how are you supposed to know the difference? 
To help you meddle through this wet mess is
Jerry
, the
trustworthy super app
for
car insurance
. In this article, we’ll review some common causes of water coming out of your exhaust pipe: which are normal and which should lead you to call up your local mechanic. We’ll even show you some of our best tips to keep your vehicle-related expenses low. 
Don't get ripped off!
Estimate repairs near you with GarageGuard™ for free so you KNOW the fair price.
No spam or unwanted phone calls · No long forms
No spam or unwanted phone calls · No long forms · No fees
icon4.717k Ratings
5M+Drivers Joined
7M+Cars Garaged

Causes of water coming out of your exhaust pipe 

To understand why there’s water dripping out of your tailpipe, you first need to know a thing or two about your car’s combustion process. When you put your key into the ignition and give it a twist (or push to start, if you’ve got a newer model), a spark ignites the combustion in your engine cylinders. The cylinders, which contain pistons, burn fuel and convert it into energy that powers your wheels. 
The combustion process is long and complex, but we don’t need to get into the nitty gritty of it here. What’s important is that this process creates water vapor and carbon dioxidebyproducts, and these byproducts need to be expelled from your engine one way or another. 
Enter: the exhaust system. Your exhaust systemremoves these byproducts from the combustion chamber to keep them from gunking up your engine. Finding a little bit of water in your car’s exhaust pipe usually doesn’t mean there’s a major problem—but a lot of water could indicate a problem. 
Let’s review five possible causes of water dripping from your tailpipe, and the signs of a more serious problem. 

Water condensation in the car engine

Water vapor and other exhaust gasses are normal byproducts of the internal combustion process, and they are removed from your engine through the exhaust pipe while your engine is running. As your engine cools, the water vapor mixes with the exhaust gasses to form water condensation.
These water droplets accumulate along the tailpipe and can be noticed once your engine is completely cool. However, once you get your engine running again, they should disappear. Seeing water droplets on your tailpipe is especially common in colder environments, where your engine is more likely to cool off faster than it would in a warmer climate. 
So,water condensation in the car engine is completely normal, and shouldn’t leave you scrambling to call a mechanic. 
MORE: How much water damage will total a car?
Don't get ripped off!
Estimate repairs near you with GarageGuard™ for free so you KNOW the fair price.
No spam or unwanted phone calls · No long forms
No spam or unwanted phone calls · No long forms · No fees
icon4.717k Ratings
5M+Drivers Joined
7M+Cars Garaged

Engine overheating and coolant leaks

If your engine is overheating and you’re noticing water dripping from your exhaust pipe, you could be suffering from a coolant leak. Coolant, also known as antifreeze, circulates throughout your engine to keep the internal operating temperature stable. Without it, the engine heat will be too high and you run the risk of doing long-term damage to your engine.
Coolant leakage can be caused by a number of different things, like a crack in the coolant reservoir, engine block, or cylinder. If you suspect the problem is with one of the cylinders, you can perform a compression test on each one. And if the test yields low results, odds are, one of your cylinders is sporting a crack. 

Catalytic converter

Your catalytic converter is a vital part of what makes your vehicle more eco-friendly. It’s bolted onto the exhaust pipe and helps convert the more toxic byproducts of the combustion process, like carbon monoxide, into less harmful emissions to reduce the number of pollutants in the air. 
Water vapor is a natural byproduct of this purification process—so there’s no need to sweat seeing a small amount of water dripping from the catalytic converter/exhaust pipe area. While a little bit of water is completely normal and to be expected, excessive water could point to a much larger problem.

Blown head gasket

If you seelots of water pouring from your tailpipe and white smoke coming out, it could be a blown gasket head. The gasket functions as a physical barrier between the internal combustion chambers to keep any oil, coolant, or other contaminants out and the combustion gasses in. If the engine overheats or if the water pump fails, the gasket head is likely to fail.
The gasket head is a small but important part of your engine, but unfortunately, it won’t last forever. Over time, the seal can develop leaks (or become “blown”), which allow combustion gasses to leak out of the chamber and coolant, oil, and other contaminants to leak in. 
When this happens, you will notice white smoke coming from your tailpipe, and there will be air bubbles in the coolant reservoir, lower than normal oil and coolant levels, and oil and coolant dripping from your tailpipe. 
Although the gasket part itself is relatively inexpensive, the cost to fix a blown gasket head can get very expensive. On average, it’s estimated that a blown gasket head costs between $1,000 and $2,000. Replacing a gasket head is a very labor-intensive process—labor which you’ll see reflected on your mechanic bill. 

Faulty pistons

A bad piston, or bad piston rings, are more expensive and complex fixes. The pistons are housed inside the cylinders that are a part of the internal combustion engine. Pistons are pushed up and down by the combustion process in order to drive the crankshaft, which is sent to the transmission and ultimately to your wheels. 
Piston rings sit between the pistons themselves and the walls of the combustion chamber to keep the pistons from touching the interior walls of the chamber and to help seal the chamber. If the piston rings and the gasket head fail, you’ll see water leaking out of your tailpipe. But, if just the pistons or rings themselves break, you’ll also notice blue smoke and a burning or sweet smellcoming from the engine. 
Depending on the extent of the damage, it could cost as little as $1,000 or all the way up to $5,000. Kind of like the gasket, the piston ring itself isn’t that expensive of a part (it usually costs only about $100), but piston repair requires nearly 15 hours of mechanic’s labor. 

Find hassle-free car insurance

Pinpointing the cause of why water is dripping from your exhaust pipe can be an time-consuming process with a hefty
car repair
bill. But, thankfully, shopping for a
car insurance
policy doesn’t have to be when you shop with
Jerry
.  
If you’ve never heard of Jerry, allow us to make the introduction: Jerry is a
trusted insurance comparison shopping app
that finds drivers customized quotes on car insurance in a matter of minutes. 
Gone are the days of endless online research, hours of waiting on hold, and overpaying for your coverage needs. All you need to do is download the app for free from the app store, take 45 seconds to answer some basic questions, and watch as Jerry pulls customized quotes for you across premium insurance providers.
And, just because Jerry is an app doesn’t mean that you’ll go through the insurance shopping process alone. If you ever have questions, Jerry’s team of rockstar insurance agents are only ever a text message away.
 “You must get this app! It’s my first time getting my own insurance, so I called a few companies myself. Their rates priced me around $600/month. I used
Jerry
and my rates went down to $250/month. I’m so happy!” —Melissa C.
RECOMMENDED
Jerry automatically checks if you are paying the lowest price for your insurance, for free.
Instantly compare top insurance companies
No spam or unwanted phone calls · No long forms
What insurance do you want to compare?

FAQs

The water coming out of your exhaust pipe is, most of the time, a completely normal byproduct of the engine’s internal combustion process. While operating, your engine creates exhaust gasses and water vapor that need to be filtered out through the tailpipe.
If the water coming out of your tailpipe is colored, there’s a chance that it's not even water to begin with. In this instance, it’s more likely to be blue, green, red, purple, or orange and have a strong sweet smell to it.
Estimate your repair costs for free with GarageGuard™
Simplify your car maintenance with Jerry.
Try GarageGuard™

Easiest way to compare and buy car insurance

√
No long forms
√
No spam or unwanted phone calls
√
Quotes from top insurance companies
Find insurance savings