What does the engine MIL light mean?

[Douglas]

Engine MIL light indicates an engine malfunction. Below are specific explanations of the causes and solutions: Spark plug carbon buildup: Carbon buildup is a residue produced during engine operation when fuel does not fully combust under high temperatures. If not expelled with the exhaust in time, it accumulates in various parts of the system, forming a black, charred substance known as "carbon buildup." When carbon deposits form on spark plugs, they create an insulating layer on the electrodes, making it harder for high voltage to break through the medium between them. This increases the required ignition voltage, reduces ignition success rates, leads to poor engine combustion, higher fuel consumption, and insufficient power. Severe carbon buildup may even prevent ignition entirely, ultimately causing the engine to fail to start. Solution: Remove and clean the spark plugs. Poor fuel quality: When refueling, if the fuel quality is poor, the fuel supply system is most affected. Low-quality fuel often contains excessive gum, which can clog the vehicle's fuel filter and fuel injectors. This results in poor fuel supply, making acceleration sluggish. In severe cases, it may cause sudden engine stalling or fuel cutoff, potentially leading to other serious consequences. Solution: Choose high-quality fuel.