Drivetrain Exhaust and Water
Exhaust and Water
Ive notice that a lot of water gets released out of my performance exhaust when the car is cold. I know cars do this, my previous car didnt do it as much. Do others also experience this?
Normal, don't worry about it.
Due to the way different exhaust systems are built, some cars don't actually push it out till you're running down the road, that's probably why you didn't see it with your other car.
Due to the way different exhaust systems are built, some cars don't actually push it out till you're running down the road, that's probably why you didn't see it with your other car.
A lot of people don't know this, but water is a by-product of combustion and so is present in the exhaust all the time. When the car's cold, the exhaust pipes themselves cause the water to condense from steam/vapor into liquid. The gas pressure then pushes this out the back.
This is also how you can tell if the car in front of you in winter was just taken on the road (visible water vapor in the exhaust) or has been warmed up (less visible water vapor).
This is also why exhaust systems last longer on cars that are driven on longer trips. Getting the exhaust fully warm will evaporate the water left in the exhaust. That "water" is actually pretty contaminated with carbon dioxide (and other stuff), making it acidic/corrosive. Burning it off (vaporizing it, really) with a hot exhaust makes sure it's not just sitting in there, acidly eating away the car's innards. Short drives (where the exhaust pipes themselves don't get really hot), and especially short drives in winter, will result in more liquid water being pushed out on subsequent startup.
Just little stuff that's stored in my brain. Scary place.
This is also how you can tell if the car in front of you in winter was just taken on the road (visible water vapor in the exhaust) or has been warmed up (less visible water vapor).
This is also why exhaust systems last longer on cars that are driven on longer trips. Getting the exhaust fully warm will evaporate the water left in the exhaust. That "water" is actually pretty contaminated with carbon dioxide (and other stuff), making it acidic/corrosive. Burning it off (vaporizing it, really) with a hot exhaust makes sure it's not just sitting in there, acidly eating away the car's innards. Short drives (where the exhaust pipes themselves don't get really hot), and especially short drives in winter, will result in more liquid water being pushed out on subsequent startup.
Just little stuff that's stored in my brain. Scary place.
Thanks for the good explanation, DixonL2. Said better than I.
The Invidia exhaust I bought had a carbon-like coating on it. When it was first installed, the system produced alot of smoke as it burned off. I was told this helps coat the interior surfaces to help with longevity against the moisture buildup.
The Invidia exhaust I bought had a carbon-like coating on it. When it was first installed, the system produced alot of smoke as it burned off. I was told this helps coat the interior surfaces to help with longevity against the moisture buildup.
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