5 Reasons Why Water is Coming From Your Car Exhaust
Seeing water drip from your tailpipe can be alarming but isn’t always serious. In some cases, condensation buildup is normal. In others, it signals major engine issues like a blown head gasket.
This article explores the possible reasons for water in your exhaust, from harmless to hazardous, so you can assess the severity and know if repairs are needed.
Read Also: 6 Reasons Why Oil is Coming Out of Your Exhaust
Top 5 Causes of Water Coming Out of Your Tailpipe
#1 – Engine Water Condensation
When your engine goes through the internal combustion process, there are various pollutants that form. The three main pollutants are water vapor, nitrogen, and carbon dioxide.
As the exhaust gases are leaving the chamber, the carbon dioxide and water are getting mixed together. The more the engine cools down, the water condensation in the exhaust becomes visible to those from the outside.
The tailpipe will have small drips of water coming out of it. When this happens, you have nothing to worry about. The water drips should stop within a couple minutes once the vehicle is warmed up.
#2 – Hot Engine
Your engine will generate the most heat when you first start your car. The oil in the engine still needs time to flow and lubricate the components to cool them down. But, while the engine is hot, the exhaust system will be hot as well.
This will create water vapor in the exhaust if the temperature outside is cold. As a result, water droplets will come out of the tailpipe for a couple of minutes and then clear up. If they don’t clear up, then it could mean big trouble.
#3 – Catalytic Converter
Every car has a component called a catalytic converter. This component lowers the amount of toxic gas emissions being emitted from the exhaust system. That way, the emissions are not as harmful to the environment or people.
During the conversion process, traces of water vapor are produced. This will result in water droplets falling out of the tailpipe which again should go away on its own and perfectly normal.
#4 – Head Gasket Failure
The first three reasons listed here are generally no cause for concern. The time when you should start worrying is if the water coming from your exhaust is caused by blown head gaskets.
Blown head gaskets will often manifest as white smoke coming out of the tailpipe. You may also notice air bubbling in the coolant reservoir and overheating issues. This issue should be addressed sooner rather than later. An overheating engine can cause all sorts of issues, and may even leave you stranded.
#5 – Bad Pistons or Rings
A bad piston or worn piston rings will generally not cause water out of the tailpipe unless the head gaskets are also blown, or there is residual condensation in the exhaust system. However, bad pistons or rings will cause excessive blow by, which could create sooty exhaust, blue smoke, or oily residue around the tailpipe.
As with blown head gaskets, you don’t want to let this one go too long without a repair, either.
Conclusion
Most of these reasons are due to water vapor effects. If it is cold outside in your environment, your tailpipe and the other components of your vehicle are going to be cold. This means that the heat generated from your engine while it is running will cause water condensation to form wherever there is water vapor present.
Since water vapor is commonly found in the exhaust system, then this is why so much of the water condensation flows out of the tailpipe.
He’s known for his attention to detail and problem-solving skills and enjoys coming up with out-of-the box solutions when the situation requires it.
When he's not troubleshooting customers' cars, you'll most likely find him working on his current project ('96 Bronco) or cooking Italian food for his family.
- Replace the Engine or Replace the Car? (11 Factors to Consider) - Apr 11, 2024
- Plastic Piece Dragging Under Your Car? (What It Is and What To Do) - Mar 21, 2024
- Timing Belt vs Timing Chain (What’s the Difference?) - Feb 27, 2024
I have a Peugeot 208 GTI 2014. Coolant needs top up constantly, white steam coming from exhaust, also exhaust smells sweet when running for a while. Can i see if gasket is blowing through 1 of my sleaves with a pressure test? If i pressure test my cylinders? Don’t want to take it in for new head gasket as it is very expensive, not alot of workshops work on Peugeot’s here in South Africa. Want to be dead sure before sending it in for any tipe of repairs. Other tipe of tests i could do to determine if my head gasket has blown? Or find out where my coolant is disappearing to?
Thanx in advance
Yeah, probably the best test for you would be a leak down test. This is a sort of pressure test that pumps compressed air into each of the cylinders. You can measure “leak down” (how much each cylinder leaks), but where the air is leaking can tell you a lot about your engine.
If you see air bubbles in your cooling system while performing this test, chances are really good that you have a head gasket leak. It’s possible to have a cracked head or cracked block and see air bubbles in the coolant as well, but these issues are less common than a blown head gasket.
Hello, just wondering if you could tell me if this is a serious enough issue. where I shouldn’t go anywhere until it’s fixed or figured out? Don’t want to end-up stranded. Recently my son changed my spark plugs for me but, they were soaked in oil, he of course told me what he thought might have caused this, we cleaned up the excess oil, put new spark plugs in, but when starting it white clouds of smoke came out and now there is water/oil mix maybe? coming out of the tail pipe. What could be the issue now? Not safe for me to drive? leave me stranded?
What makes you think there is water/oil mix? Just the white smoke?
How far are you planning to drive the car? There’s really not enough information for me to say if the car will break down or not. More troubleshooting is likely needed.
Car was recently serviced. Asked for coolant drain and replace. Now it seems the coolant level is dropping rapidly for some reason. Oil looks normal. Water looks normal – some signs of bubbly foam. Engine is running smoothly and there are no signs of any water leak other that at the exhaust which is probably just condensation of exhaust gases. Any ideas on what’s causing the drop in coolant level ?
Sounds like something is leaking. You could have a coolant leak even if you don’t see anything. Sometimes a leak will show up as white streaks around the source of the leak. I’d take it back to the shop, tell them the problem, and ask them to take a closer look. Mistakes happen, and they can double check their work. Shouldn’t cost anything.
Hi my bmw 328i isn’t loosing coolant no overheating..but white smoke from exhaust even after driving for 30 minutes, it’s -3 Celsius outside. Is it normal
In cold temperatures, yes that’s perfectly normal. You will see a lot of white “smoke”, which is probably actually condensation from the hot exhaust against the cold air. It’s just like when you see fog from your breath in those temperatures.
Hi it’s my daughter s car ford focus 1.00 ltr eco boost. Running hot loosing water through exhaust expansion tank level dropping no leaks anywhere except exhaust
Is the car overheating? Any white smoke? You can do a leak down test to help narrow down where you’re losing water. Could be a head gasket failure. I don’t know for sure if the intake manifold has water jackets on this model, but if it does you could just need a new intake manifold gasket.
Probably best to take the car in, have a shop take a look and see what they say.
I adjust timing polo 1.6i now it dont idel and petrol smell
Double check your work, and make sure it is timed according to factory specifications. Sounds like some of the fuel isn’t burning completely because the timing is off.
I have a Hyundai getz that is spraying water out of the exhaust :(. I believe the head gasket was welded before I bought the car. The car has given endless problems, from jerking, to cutting out, to not starting. Now the problem is to start it and when it does start the water comes gushing out the exhaust. What do I do?
Is there any white smoke, or just water? If you see water alone, it does not necessarily mean there is anything wrong with the car. The best thing you can do is have a mechanic look at the car in person. It’s hard to describe how much water you’re seeing over the internet.
i have a slightly smoky exhaust with white fumes whenever i start the car and it disappears with time. there are few drops of water leaking out of the tail pipe as well occasionally. don’t know if it calls for concern
It’s probably not cause for concern if that is the only odd thing you notice, especially if it is cold outside. I would be more concerned if the car was also overheating, running low on coolant, or losing oil.
Water dripping out of where my exhaust pipe where they come together as one. Dripping fairly heavy. Something I need to be concerned about ?
Sounds like you may have an exhaust leak, for water to drip out of the middle of the exhaust like that. Are you sure it isn’t water coming from above the exhaust and following the curvature of the exhaust pipes?
Best to get it checked out so you know for sure.
when I rase my car in the morning smoke is coming out ,and water is still coming out of it, but when is working the smoke we disappear
Is it cold outside? Sometimes vehicles appear to smoke a bit when it’s cold outside just because of the condensation. It could just be the hot exhaust interacting with the cold air around it.
If you’re worried the smoke is excessive, it won’t hurt to have the vehicle inspected.
I have a F150. A year ago had the trans rebuilt. Just after that was having issues with running very rough. Took to a local shop and replaced everything ‘running’ related. Turns out it was bad gas from being parked for so long. Dropped the tank and emptied almost all the bad gas. Reinstalled tank and filled it with premium and octane booster and stabilizer. Start it once a week and sometimes on the road. A couple of weeks ago started running very rough, even more than usual. This morning started it up to run and noticed ‘drainage’ out of various joints in the exhaust system and I mean drainage. Felt clean, no oil, no antifreeze and no smell. What’s up?
I’m not sure. Are they coming out of joints in the exhaust like you have an exhaust leak and water is leaking out of the holes? I’m not sure I understand.
Steam like vapor from tailpipe old car 2000 Atos had headjob piston rings changed not coverheating no cracks seen but still vapor smoke cno smell and drops of water from exhaust what can it be?
A little bit of water from the exhaust is normal and no cause for concern. Does it look like smoke?
Mine is, I usually observe vapour and water dripping from the tailpipe particularly when the weather is cold. I also feel if oil is coming out as well but I haven’t observed such anyway
If its like 5 degrees celsius and quite moist out not raining, could that cause water leaking from my exhaust? I didn’t wait to see if it went away because it felt like gas on my hand but didn’t smell like it, smelt like nothing.
Yes, this is probably not a cause for concern.
Just had a blown head gasket in January2021, the cylinder head was replaced and the car was driving well, now excessive water is coming from the exhaust when I start the car, I checked the oil cap it looks ok. What could it be? Its a BMW 318 face lift 2002
I don’t know. Under some conditions it’s perfectly normal to see a bit of water coming from the exhaust. White smoke would be cause for concern. If you’re worried the head gasket has blown a second time, you could do a leak down test to help you confirm this.
You have a clog in your coolant system and the water is escaping as a vapor through your radiator cap. More than likely your radiator is clogged up from too much water and not enough antifreeze in the system
So I have to ask where all of my coolant goes?
Not in the oil Pan nor tans pan
Bubbles and pressure from a cool system
Engine clatters and loses power
Have I went too far with my problems?
I’m not sure I understand. It’s probably best to bring it to a shop for a diagnosis of the issue.
Your pistons and rings are not what’s causing water vapor to come out of your exhaust no matter what. What you mean is, your head gasket is bad that’s the only reason why water should be getting into your exhaust other than normal, than normal condensation.
Good catch, thanks. You are correct: in the case of bad rings, it would actually be oil coming out of the exhaust, not water. I’ve updated the article.
If I have a blown head gasket then wouldn’t my oil be milky?
Not necessarily. It depends on how the head gasket is leaking. I have had a blown head gasket without any symptoms other than occasional overheating.
Is that something to be worried about?
Water vapor from the exhaust? Usually no. Head gasket failure? Usually yes.