And what is it? Always assumed it was just water but now I’m pretty sure it’s not. Also do all cars do this?
One byproduct of combustion is water vapors. As molecules get rearranged during the combustion process you are using heat to make the gasoline (a HYDROcarbon, i.e. hydrogen and carbon) react with OXYGEN. So some of it comes out with the hydrogen binding with oxygen creating H2O (water, hydrogen and oxygen) , and others are CO or CO2 (Carbon and oxygen) the leaner the mixture the more likely you get the relatively harmless co2 instead of the deadly CO because the more oxygen rich mixture allows for mpre complete combustion with two oxygen molecules to bind to it making co2 instead of just one binding to it making CO.
Anywho, those water vapors condense when the exhaust and engine cool into actually liquid since colder air can’t hold as much moisture as the normally hot exhaust. When you start the car that condensed water gets blown to then end of the exhaust and drips out.
I am probably not 100% accurate on the chemistry, I am just a firefighter that likes to also work on cars. I understand how fire works.
Isnt it sometimes gas?
No, if your car was built in the last 50 years it probably has a catalytic converter, which will burn off any fuel that hasn’t combusted before it gets out of the exhaust. And even so, once you get to the point where you’re having fuel flow out the exhaust it would be flooded to the point well beyond hydro-lock and wouldn’t be running at all.
If your engine is working very poorly. Unburned fuel in your exhaust is a problem large enough that you’ll probably be experiencing a lot of engine trouble.
And explosions in the exhaust (backfires)
Great explanation, relatively simple
Gas to water phase change. Otherwise known as condensation
This is normal, and all cars actually do it.
In 99% of cases, water from your car exhaust system is absolutely normal and is nothing to worry about. It is just condensation being vented while the engine is running. You’re most likely to notice this when the outside temperature is cold and when the engine has not been running all that long.
I don’t think EVs do it
Edit: downvotes from people who completely lack a sense of humor
I didn’t know ev’s had exhaust.
They don’t, hence my comment.
I know, hence my comment.
This thread is on no stupid questions. Why go out of your way to be rude/smart ass?
You’re projecting quite a bit onto me. Maybe you should take the day off.
Your edit speaks volumes. I didn’t down vote that one btw. It was fine enough. I was playing stupid to continue what I thought was joke.
And that’s why you started acting like a jerk?
It is just water. When the engine starts the cold exhaust heats up creating condensation which drips off as the exhaust fumes are expelled.
It “can” be oil, but you’d need to be pretty unlucky, and need a new engine.
And then it wouldnt “just” be oil, it would be belching out smoke too.
