Exhaust Smoke Colours and Pollutants

Did you know that cars emit smoke with a differnt colour depending the engine that they use and the problems that they are having. Here are the following categories: Blue smoke, White smoke and Black smoke.


Blue Smoke

Blue smoke means your engine is burning oil. Oil is an important element in the engine, but only to lubricate the moving parts. When it is burnt by the engine means that there are leaking valve seals or worn piston rings or worn cylinder walls. In this case large quantities of Carbon monoxide CO, PMs, NO2 and SO2 are released into the environment.

White Smoke

There are two types of white smoke, the normal white vapor that disappears quickly under normal conditions due to condensation and the heavy white smoke. The heavy white smoke must concern you because the coolant has made its way into the combustion chamber. In this case large quantities of VOCs and PMs are released into the environment.

Black Smoke

Finally the black smoke indicates that your air/fuel mixture is running rich. Which means that more fuel is entering the engine and it doesn’t burn completely due to the lack of the air or oxygen. This is also called rich. When more air enters the engine than fuel this is called lean. In this case large quantities of CO, PMs and NO2 are released into the environment.


All in all, the emitted smoke from the exhaust may not tell you the exact problem, but it can give you an idea of what the problem of your engine is and the pollution that is emitted. Visit your mechanic immediately, public health may be in jeopardy.