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The history of spark plugs is traceable to the 1800s, although it isn’t certain who invented the first one. Edmond Berger, an immigrant from Togo, may have created a sparking plug in 1839.

Unfortunately, it was never patented. While others had a hand in developing the spark plug, Robert Bosch was the one to perfect and patent the technology. More than likely, your personal vehicle has spark plugs, although diesel engines and electric cars certainly do not have them.

History of Spark Plugs

Before the spark plug came into use, manufacturers relied on other sources, such as car batteries, to generate ignition. However, tapping car batteries seriously depleted power and in some cases caused fires. The German inventor, Robert Bosch, developed the first functioning spark plug in 1901, then received a patent the following year.

Today, spark plugs are a necessary part of the internal combustion, or gas engine, as they supply ignition for the combustion required to start these vehicles. On ignition, the air-fuel mixture travels to the engine cylinder where it’s ignited by the spark created by the spark plug. This is precisely what so many people before Bosch attempted, but only one individual saw it to a successful conclusion.

Diesel engines don’t have spark plugs because they rely on the compression stroke to raise the air temperature in the cylinders ahead of injecting the fuel. Electric cars don’t use fuel at all, relying on complex battery systems to supply propulsion.

As for your gas-powered vehicle, the spark plug may be small in number but it is mighty in deed. Without functioning spark plugs you aren’t going anywhere.

Spark Plug Location

Locating your spark plugs is as easy as lifting the hood and eyeing the engine. In vehicles equipped with a four-cylinder or engine, the spark plugs sit on the top or the side of the engine, all in a row. Cars with V6 or V8 engines typically have spark plugs evenly separated on each side of the engine. You’ll find one spark plug in each cylinder.

In older vehicles, each spark plug connects to a spark plug wire, which connects the top of the plug with the distributor. In vehicles without a distributor, there are no wires. Instead, ignition is achieved by means of coil packs and toothed timing wheels spinning inside the crankshaft, which is a more accurate method than ignition points. The entire system is managed by a computer. Most modern vehicles do not have a distributor, therefore the latter arrangement is typically utilized.

When Spark Plugs Fail

Copper spark plugs typically last for 20,000 miles, while the platinum spark plugs found in most cars are usually good for 60,000 to up to 100,000 miles. Trouble signs include engine misfiring, rough idling, engine surge, lack of power when accelerating and decreased fuel economy.

Your owner’s manual lists the maintenance intervals for spark plug replacement. Follow the guidelines and you’ll avoid trouble, including a possible breakdown.

Check out all the electrical & ignition system products available on NAPA Online or trust one of our 16,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on the history of spark plugs, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

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