Exhaust smoke
In an efficient internal combustion engine, be it a gasoline or diesel engine, colorless exhaust gases must flow from the exhaust pipe.
If everything is different and there is blue, black or white smoke coming from behind the car, this indicates an engine malfunction. And by the color of the smoke, you can diagnose the type of malfunction in advance.
blue
If blue smoke comes out of the exhaust pipe of a gasoline or diesel engine, unfortunately, this is a sign of wear and tear, as engine oil burns. If we have any doubts whether it is really oil, we must check the oil level in the engine. Its rapid exhaustion, combined with the blue smoke from the chimney, is unfortunately indicative of engine damage. Under what operating conditions of the engine smoke appears, it can tell about the nature of the damage. If the smoke is not visible at idle, but appears when the engine speed is reduced, this may be a sign of wear on the valve stem seals. If smoke appears at idle and with increasing speed, this is a sign of wear on the piston rings and the working surface of the cylinder. In turbocharged engines, blue smoke can be caused by damage to the turbine.
white
White smoke from the exhaust pipe also does not bode well. If there are no leaks from the cooling system, the liquid disappears and white smoke comes out of the exhaust pipe, unfortunately, this indicates that liquid has entered the combustion chamber. This could be caused by a damaged cylinder head gasket, or worse, a cracked head or engine block. Smoke from coolant is much denser than water vapor coming out of the exhaust, which is a normal product of combustion and is noticeable at low temperatures.
the black
Black exhaust smoke is the lot of diesel engines. Most often this happens at high load and high speeds. A little smoke is acceptable and does not necessarily mean that the injection system is worn out. However, even if a small addition of gas results in the formation of clouds of smoke, this indicates a serious malfunction of the injection system. Injector tips may need to be adjusted or replaced, the injection pump may be faulty or the exhaust gas recirculation system may be faulty. It is necessary to carry out a detailed diagnosis, since the repair of the injection system is very expensive, especially if it is a modern design with unit injectors or a common rail system.
Black smoke can also appear in a gasoline engine if there is damage to the engine control system and a very rich fuel mixture enters the cylinders. The smoke will be low, but it will be visible even at idle.
