What is the reason for the smoke in the car?

The causes of black smoke are: 1, and the causes of black smoke are insufficient fuel combustion or unclean air filter, poor spark plug, etc. 2. It is normal for the engine to emit a little white smoke when the climate temperature is low in winter. If a lot of white smoke is emitted, it is because the engine cylinder and waterway are flooded, which affects the cooling water entering the engine and evaporating into steam at its high temperature; 3. The blue smoke is caused by the use of unqualified engine oil, which has not been replaced for a long time, and the conduit and throttle of the engine compartment are worn.