If the engine is smoking due to overfilled oil, it is recommended to drain some of the excess oil to bring it back to the normal level. Generally, if white smoke continues to appear from the car engine even when it's hot, there may be two possible causes: a small injection advance angle leading to incomplete combustion, or a slight water leak in the cylinder liner or water in the fuel. However, white smoke during cold starts, especially in low temperatures, which disappears as the engine warms up, is a normal phenomenon. Black smoke from the car engine can occur under the following conditions: an imbalance in the air-fuel ratio; decreased cylinder pressure; overly advanced injection timing (excessive injection advance angle) can cause black smoke; failure of the smoke limiter on the injection pump can also result in black smoke during rapid acceleration; or malfunctioning of the exhaust brake system. If severe black smoke is observed, other issues should also be considered. Precautions: Choose engine oil based on the engine's requirements. Do not use high-grade oil in a low-performance engine, nor low-grade oil in a high-performance engine. Select oil that matches the engine. Multi-grade oil is recommended as it offers advantages such as fuel efficiency, long service life, and high performance, providing better protection for the engine. The oil level should be slightly below the mark on the dipstick and not overfilled. Excess oil not only increases the crankshaft's rotational resistance but also reduces the engine's output power. Moreover, the excess oil may enter the combustion chamber and participate in combustion, leading to oil burning, blue smoke, and increased fuel consumption.
