Why from the exhaust pipe can “go black smoke”

Why from the exhaust pipe can “go black smoke”

What does the presence of black or white smoke.

The smoke from the exhaust pipe serves as a diagnostic sign and indicates the resulting engine malfunction. Talk what does black and white smoke from the exhaust pipe of the car.

White smoke from the exhaust pipe

White smoke from the exhaust is normal for a cold engine warms up. Only it’s not smoke but vapor. Water in the form of steam — a sign of high humidity in the exhaust system. Not heated in the exhaust system moisture from the air and partially condenseries becomes visible, and the cut exhaust pipe usually appears water. As heating system the condensate and vapor disappear.

However, at temperatures below 10 º C white steam is formed and on warmed-up engine and at a frost in -20—25 ° C takes on a thick white color. So, the colder the environment, the more dense it smokes from the exhaust pipe. In addition, the color and the saturation of the vapor is affected by the humidity: the larger it is, the thicker the vapor.

The appearance of white smoke on warm engine is due to hit in the cylinders for coolant. The water contained in the coolant does not have time to fully evaporate during combustion and forms a quite thick white smoke. Its hue depends on the composition of the coolant, weather and light conditions on the street. Sometimes it looks grey, Recalling the “oil” smoke. To distinguish water vapour easy: it is at once dissipated, and after the oil smoke in the air remains a bluish fog.

It is easy to determine that from the exhaust pipe really thrown water, not oil. On warmed-up engine momentarily close the opening of the exhaust pipe with a sheet of paper. Water drop with leaf will gradually evaporate and will not leave a clear oily residue.