What is the difference between spark plugs and ignition coils?
2 Answers
Spark plugs and ignition coils differ in their functions: The spark plug is a crucial component of a gasoline engine's ignition system, which introduces high-voltage electricity into the combustion chamber and causes it to jump across the electrode gap to generate a spark, igniting the combustible air-fuel mixture in the cylinder. The ignition coil transforms low-voltage direct current into high-voltage electricity, which can reach tens of thousands of volts, and uses the spark plug in the cylinder to ionize the air and produce an electric spark. The main types of spark plugs include: 1. Standard spark plugs; 2. Insulator-protruding spark plugs; 3. Electrode-type spark plugs; 4. Seat-type spark plugs; 5. Pole-type spark plugs; 6. Surface-gap spark plugs. Ignition coils can be categorized by magnetic circuit into: 1. Open magnetic circuit type; 2. Closed magnetic circuit type.
I've been working in an auto repair shop for almost ten years, dealing with ignition systems every day. Spark plugs and ignition coils are like relay race runners. The spark plug is the final sprinter, directly extending into the cylinder, igniting the gasoline with the electric spark generated at its tip. The ignition coil is more like logistical support, responsible for boosting the battery's 12-volt voltage to tens of thousands of volts, then transmitting it to the spark plug through the ignition wire. The most obvious difference between them is their location. When you open the engine hood, you can see the ignition coil plugged into the top of the engine cover, while the spark plug is hidden deep inside the cylinder and can only be seen after removing the coil. If you feel weak acceleration accompanied by shaking while driving, it's likely that one of them has a problem.