How does a car spark plug work?

[HopeRose]

The working principle of a car spark plug is that the electrode of the spark plug repeatedly and continuously generates ignition sparks to ignite the air-fuel mixture in the cylinder. At this time, other parts of the ignition system produce a timed high-voltage electrical pulse, forming a spark and generating an explosion to provide the energy required for the engine's power output. The function of the spark plug is to introduce the high voltage generated by the ignition coil into the engine cylinder, creating a spark between the electrodes of the spark plug to ignite the air-fuel mixture. The working environment of the spark plug is extremely harsh. Taking the spark plug of an ordinary four-stroke gasoline engine as an example, during the intake stroke, the temperature is only 60 degrees Celsius, and the pressure is 90KPa, while during ignition and combustion, the temperature can instantly rise to 3000 degrees Celsius, and the pressure reaches 4000KPa.

[OElliot]

I remember having difficulty starting the car for the first time, and later learned that the working principle of spark plugs is key. When you turn the key to start the car, the ignition system sends high voltage from the battery and coil to each cylinder's spark plug, creating an electric spark between its two metal electrodes. This spark instantly ignites the fuel-air mixture in the cylinder, causing a small explosion that pushes the piston to drive the wheels. The spark plug must be designed with the proper gap to ensure stable and reliable sparks. When they age, they may fail to ignite or cause reduced power. From my experience, when spark plugs age, the car starts slowly, has higher fuel consumption, and lacks power when climbing hills. Regular inspection and replacement are crucial to maintain ignition efficiency, making the engine smoother and more fuel-efficient while reducing unexpected failures. I remember replacing the spark plugs before a long trip once, and the driving experience became noticeably smoother and safer.

[AnnieFitz]

As a car enthusiast, the working principle of spark plugs is the part that fascinates me the most. It's responsible for generating sparks inside the engine cylinder to ignite the air-fuel mixture, specifically by creating an arc between the central electrode and side electrode of the spark plug through high-voltage electricity from the ignition system. This spark triggers combustion at the end of the compression stroke, driving the piston to rotate the crankshaft. Spark plug materials like platinum or iridium affect ignition stability and lifespan, while incorrect gap width (too wide or narrow) can cause misfires or power loss. I regularly check spark plug color - grayish-white indicates normal operation, while blackening suggests incomplete combustion requiring adjustment. Upgrading to high-performance spark plugs can slightly improve acceleration and fuel efficiency. For modification enthusiasts, this is basic maintenance - never overlook cleaning or replacement during each service interval.

[MacTeagan]

During repair, the spark plug's function is to generate a spark between the electrode gaps when high-voltage current passes through its coil, igniting the fuel-air mixture to start and run the engine. The gap must be set accurately—too small risks burning out, while too large may cause misfiring, leading to engine shaking or cylinder misfires. Common issues include carbon buildup or wear, resulting in unstable ignition, increased fuel consumption, and emission problems. It's recommended to inspect spark plug condition every 20,000 kilometers and replace if necessary to prevent roadside breakdowns. Simple maintenance can extend engine lifespan.

[MacLuna]

I've noticed that spark plugs are small components in the engine that generate sparks to ignite gasoline. When the ignition coil delivers high voltage, a spark jumps between the two metal points of the spark plug, igniting the air-fuel mixture and propelling the car forward. If spark plugs are worn or dirty, the car may experience difficulty starting, sluggish acceleration, unstable idling, and increased fuel consumption risk. Based on my maintenance experience, they should be replaced every 30,000 to 40,000 kilometers, selecting the appropriate model to ensure proper gap spacing for optimal ignition. Keeping spark plugs in good condition makes driving safer and more economical, eliminating worries about sudden stalling.