How to diagnose car problems by looking at smoke
If your car's smoke is black, white, gray, or blue, it's likely that your car has a serious problem.
The process of burning the fuel and air mixture causes the vehicle to produce exhaust gas. With a normal engine operation, the fuel mixture is completely burned, the exhaust gas is usually colorless or clear white and quickly dissolves in the air. If the exhaust gas has a strange color or smell when operating, it is likely that the engine is faulty. Through the color of the car's smoke, it is possible to know the problems that the car is facing.
Car exhaust white smoke
Car engine overheats very quickly, white smoke comes out of the exhaust pipe, it may be due to the cooling system leaking coolant into the engine's combustion cylinder and a leak appearing on the gasket.

If the white smoke is thin it could be due to condensation forming in the car's components. If the white smoke is thick and cloudy it could be due to a damaged cylinder head or a coolant leak.
With diesel powered vehicles, there may be problems with the timing of fuel injection into the combustion chamber.
Black smoke
Black smoke is quite common. It can be caused by the engine burning too much fuel or the engine burning fuel too quickly. In this case, the engine air filter may be dirty or clogged, causing less air to be drawn into the combustion chamber. If replacing the air filter does not solve the problem, the fuel injectors may be the cause of the black smoke.

With diesel engines, black smoke can indicate the incorrect type of fuel being used; a clogged air filter; an oil leak or an overheating engine.
Gray exhaust smoke
According to experts, the darker the gray smoke, the more serious the damage. The cause of gray smoke can be a faulty transmission modulator, causing automatic transmission fluid to leak into the engine combustion chamber and burn. The fluid is responsible for keeping the car's mechanical parts lubricated, so if there is a leak, the components can dry out. This can easily lead to serious damage to the car.
Blue exhaust smoke
Experts say that blue smoke is usually caused by burning engine oil. The oil used to lubricate the drivetrain components may have leaked through the pipes it passes through, spilling into the engine or fuel tank.
This happens when the piston rings wear out. In this case, acceleration will produce more blue smoke.
If blue smoke appears when the vehicle decelerates, there may be a problem with the valve guides in the cylinder head.
When detecting the vehicle emitting smoke of the above colors, the owner should turn off the engine and take the vehicle to a repair facility for inspection to determine the exact cause. The longer the vehicle is left, the more difficult and expensive it will be to repair.