Why Is Water Coming Out Of Truck Exhaust?

Ever wondered why there is water coming out of truck exhaust? The internal combustion engine burns the mixture of fuel and air in the combustion chamber. The end product of the combustion is exhaust gases that are expelled through the exhaust manifold to the environment through the exhaust pipe. 

The exhaust pipe directs the exhaust gases from the exhaust manifold to the environment. Sometimes, you will note that water comes out through the exhaust pipe instead of gases. How is this possible, yet no end product of combustion is not in a liquid state? When such happens, never worry since there is a reason why. This guide explores the reasons why there is water coming out of truck exhaust instead of exhaust gases.

Why Is Water Coming Out Of Truck Exhaust?

Here are some of the probable reasons why there is water coming out of truck exhaust instead of exhaust gases.

Smoke and Water Emissions

Emitting smoke and water from your tailpipe is a major warning that your pistons or the rings could be faulty. If it is server, you will note a burning sweet smell. When such happens, take your truck for a mechanical check-up to determine and fix the cause. 


If your truck has been in a colder climate for a while, it is essential to warm it up before starting to drive. During this process, a lot of heat accumulates in your truck that is expelled through the exhaust pipe. As the heat is expelled, condensation will occur on the walls of the exhaust system, resulting in water expulsion from the exhaust pipe. When you experience such, let your engine run for a few minutes before you start driving.

Engine Combustion

A mixture of water and carbon dioxide forms whenever your engine starts. As the engine cools down, the exhaust gases leave the combustion chamber, and water and carbon dioxide condensation are likely to be noticed. In such a situation, water will be expelled through the exhaust pipe. Such water is normal, and you should not worry when it happens to your truck.

The by-product of the Catalytic Converter

The catalytic Converter is a part of the exhaust system whose primary role is to neutralize the harmful by-products of fuel combustion. When air and fuel burn, it produces harmful gases that are dangerous to the environment. Catalytic Converter, therefore, neutralizes these harmful by-products into environmentally friendly products. Water and gas will form when converting toxic wastes into non-toxic wastes. This water will drip from the exhaust system as your catalytic Converter performs its role. The expulsion of such water should not worry you since it indicates that your catalytic Converter is functioning properly. 


Water coming out of truck exhaust pipe is mostly due to water vapor effects. The tailpipe of your truck, engine and exhaust system will be cold whenever it is cold. If you start your engine in a cold environment, the heat from the engine will cause condensation to form in all the places with water vapor. In such a situation, the tailpipe of your truck will produce water. It is essential to start your truck and let the engine run before driving. Sometimes, water from the tailpipe might indicate serious issues, such as a faulty head gasket, piston, and rings. 

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