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Every vehicle needs maintenance performed at regular intervals, including your spark plugs. Inspecting them will tell you if they need cleaning or replacing and offer clues to other problems your vehicle may have. How do spark plugs work, where did the concept come from, and what is their future look like? 

How spark plugs work

A depiction of spark plugs on the side of a white building.
Spark plug depiction | Getty Images

Your vehicle’s engine is the power behind running the car you drive. However, it doesn’t start itself. It needs a spark to light the fuel/air mixture in the cylinders to get energy moving throughout the vehicle. 

When you turn the key, it activates the alternator, which sends electricity through the distributor, coil, and then to the spark plug, where it will ignite the engine. Once the engine starts, it will get the car moving down the road, provided everything works properly. Maintaining your plugs will also be essential to keep your car running smoothly for a long time to come. 

It’s essential to check your plugs every few years or so. If they look reasonably clean, check the gap to be sure it’s still in the recommended range. Replace them every 30,000 miles or if they look like they’re going bad. You can have your mechanic do it, or you can take the task on yourself if you feel up to it. 

If you choose to replace them yourself, take care to perform it properly because something as simple as cross threading the socket can damage the spark plug and possibly the engine. 

A brief history

To shed a brief light on the history of the spark plug, let’s begin in 1839, when it wasn’t used in an automobile. Edmond Berger was credited with this invention used by demolitionists to trigger explosives from a distance. However, he didn’t patent his design. That came later on by Jean Joseph Etienne Lenoir, who developed it for his crude gas-fired engine. His version was brought about in 1859. 

In 1876, a design by Nikolaus Otto was produced and used in a stationary single-cylinder four-stroke motor, which worked closely to the plugs we use in our vehicles today, according to JalopyTalk. However, the design of the spark plug had a ways to go in development. 

Nikola Tesla is known for his electrical inventions, one of which was his coil ignition, which was an electric spark plug for a gas-powered engine. Four-stroke motors still use this plug today. 

Albert Champion, who helped start the Champion line of plugs, developed a self-cleaning spark plug in 1910, which he patented in 1924. He also created other modifications throughout the years to perfect the Champion brand of plugs we’re familiar with today.

Future of the spark plug

Obviously, all gasoline-powered engines need spark plugs to start them, but how much will the plugs be needed in the future? With automakers decreasing the brand’s production of combustion engines and moving toward electric vehicles, plug sockets will no longer be necessary except in the used car market. 

Electric cars don’t need an electric spark to start them, so a set of plugs aren’t required in the EV world, which can help bring maintenance costs down for electric vehicle owners. If most automakers discontinue gas-powered vehicles, plugs will only be needed for used combustion engines on the market. Eventually, in the future, they will become difficult to find, though. 

Spark plugs have been useful for over a hundred years as engine technology developed and improved. But, as EVs are becoming more commonplace, the need for a set of plugs will start dissipating to the point where they’re no longer necessary. 


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