What does your vehicle's smoke color means?

The color of vehicle exhaust can tell us a lot about  vehicles. You can even predict the problem in you vehicle by looking at smoke color. Generally the smoke emitted by the vehicles is colourless.  But in case of problem the smoke colours may vary. The  commonly observed colours are black, white or blue etc. The smoke colour may change due to burning of other matterials i.e. lubricant, water, coolant etc along with petrol Let's see what does a particular exhaust color means. 

Smoke Color: Blue/gray

Blue exhaust

Blue/gray exhaust smoke means there may be an engine oil leak and your engine is burning engine oil. The leak could be caused by several issues like leaking valve seals, damaged piston rings, leaking cylinder head gasket or worn cylinder walls.

Smoke Color: Black 

Black exhaust smoke

It is most  commonly seen exhaust colour in vehicles. You might notice black smoke at time when you pull your choke. Black exhaust smoke can appear when the vehicle is burning too much fuel i.e the air fuel mixture is very rich.  The ideal air fuel ratio is 14.7:1. It means stoichiometrically the amount of air must be 14.7 times that of the fuel. If the amount of fuel becomes greater than this, the mixture becomes rich and burning of rich mixture produces black smoke. Other reasons for black smoke may be   a blocked air filter, malfunctioning fuel injection system and a blocked manifold etc. All these may choke air supply to the combustion chamber and cause rich mixture to burn inside it.

Smoke Color:  Thick white/gray 

White exhaust gases

The white smoke may be caused due to water vapor . It means that some water is present inside and is coming out as vapor. This occurs only at the starting of vehicle and stops after some times.

But a steady stream of thick white/gray exhaust smoke coming from your muffler could mean there’s a leaking head gasket. In this case the coolant may be leaking and burning inside combustion chamber. A coolant leak in the summer could easily lead to an overheated engine.

Heavy white/gray exhaust smoke  could also mean a cracked block or cylinder head—both very serious problems that should be addressed quickly.