The car engine is the part responsible for generating the energy needed to move the wheels, as it mainly depends on drawing a mixture of air and fuel and compressing it to generate high temperatures before a spark is used to burn the fuel and use the burning energy to spin while eliminating the burning fire in the form of fumes and exhausts towards the outside air.
This burning mixture that comes out of the rear exhaust pipes is often a strong indication of a problem of some kind in the car engine, through the color of the fumes, as if you notice that the color of the fumes is white or looks similar to water vapor, then this is normal in Cold weather, but in the event that the steam is thick, we will find that this indicates that cold water enters the penetration chamber, and here there is a real problem in the cylinder head that may suffer from a crack.
As for the black exhaust color, it indicates evidence of sudden burning of a large amount of fuel in the combustion chamber, which may be due to a problem in the throttle valve or a leak in the injector, and possibly increasing the pressure of the fuel supply system.
Finally, the exhaust smoke may sometimes appear in a grayish-blue color, which indicates oil burning after reaching the combustion chamber and the piston rings are lost.