What's the reason for engine smoke?
1 Answers
Here are several situations where an engine emits smoke: 1. Generally, if a car engine continues to emit white smoke in a hot state, there may be two scenarios: the fuel injection timing is too early, leading to incomplete combustion; or there's a minor water leak in the cylinder liner, or the fuel contains water. However, white smoke during cold starts, especially in low temperatures, is normal if the smoke disappears as the engine warms up. 2. Black smoke from a car engine can occur in the following situations: an imbalance in the air-fuel ratio; a drop in cylinder pressure; overly advanced fuel injection timing (excessively large fuel injection advance angle) can cause black smoke; failure of the smoke limiter on the fuel injection pump can also result in black smoke during rapid acceleration; or malfunctioning of the exhaust brake system. If there's severe black smoke, other issues should also be considered. 3. Blue smoke from a car engine is often due to "burning oil." In such cases, check if the engine cylinder liner is worn, if there's "sticking rings," ring alignment issues, aging or deformation of valve seals, excessive valve guide clearance, etc. This is often accompanied by crankcase blow-by. Severe oil discharge from the turbocharger can also cause some oil to enter the cylinder through the intake tract, resulting in "blue smoke." Therefore, during routine maintenance, check the turbocharger's oil discharge and promptly clean any oil in the connecting line between the turbocharger and the intercooler.