What impact does water ingress into spark plugs have on the engine?
1 Answers
Water ingress into spark plugs does not affect the vehicle as long as the engine starts normally. The spark plug is a crucial component of the gasoline engine's ignition system. It introduces high voltage into the combustion chamber, causing it to jump across the electrode gap to generate a spark, thereby igniting the combustible air-fuel mixture in the cylinder. The spark plug mainly consists of a terminal nut, insulator, terminal stud, center electrode, side electrode, and shell. Spark plugs are installed on the side or top of the engine. Early spark plugs were connected to the distributor via ignition cables, but over the past decade, most car engines have switched to direct connection between the ignition coil and the spark plug. Under high voltage, the air between the center electrode and side electrode of the spark plug rapidly ionizes, forming positively charged ions and negatively charged free electrons. When the voltage between the electrodes reaches a certain level, the number of ions and electrons in the gas increases like an avalanche, causing the air to lose its insulating properties. A discharge channel forms across the gap, resulting in a "breakdown" phenomenon. At this point, the gas becomes a luminous body, known as a "spark." Along with thermal expansion, a "crackling" sound is also produced. The temperature of this electric spark can reach 2000-3000°C, sufficient to ignite the air-fuel mixture in the cylinder's combustion chamber.
