Your Beginner’s Guide To Spark Plugs

Spark plugs may be one of the most under-appreciated components of a vehicle. Without them, your car can’t run. And while they are essential, many drivers don’t know what spark plugs do or how they work.

This guide will share necessary details about spark plugs and their benefits.

How Does a Spark Plug Work?

The ignition coil’s high voltage is carried to the spark plug through the boot and wire. The spark gap is formed by a tiny space between the electrode and the ground. When the voltage is high enough, a spark will jump across the gap and ignite the air-fuel mixture in the combustion chamber.

What Are Spark Plugs Made of?

Spark plugs are made of ceramic insulation material with a metal shell threaded into the engine. The spark plug’s tip, which is also the part that ignites the air/fuel mixture, is made of a precious metal. Platinum and iridium are common materials used for the tip.

Main Components of a Spark Plug:

Although tiny, spark plugs are made of several vital parts that work together to do their job.

The Metal Shell: This part is what threads into the engine. It also helps to ground the electrode that protrudes from the bottom of the plug.

The Insulator: The ceramic material that makes up the plug’s body. Its primary purpose is to keep the electrode isolated from the metal shell.

The Terminal: This is where the spark plug wire attaches to the plug. This connection must be tight and free of any corrosion.

The Seal: The rubber material helps keep oil and debris from the spark plug hole.

The Center Electrode: This part protrudes into the combustion chamber and ignites the air/fuel mixture.

The Ground Electrode: Also called side, or earth, electrode. Connects to the engine’s ground to complete the circuit.

Types of Spark Plugs:

Each vehicle has specific spark plug requirements. Some plugs have a longer service life than others.

Copper Spark Plugs:

It is the most popular and inexpensive plug on the market. While virtually all spark plugs have a copper core, many refer to the average spark plug as a “copper” spark plug.

A typical spark plug is constructed of nickel-alloy outer foil welded to the copper-core electrodes. Copper spark plugs can last up to 20,000 miles before they need to be replaced.

Platinum Spark Plugs:

Platinum-tipped spark plugs are used in many newer vehicles. These have a platinum disc welded to the end of the center electrode that extends into the combustion chamber. The platinum helps to increase the durability of the spark plug, allowing it to last up to 100,000 miles before it needs to be replaced.

Platinum spark plugs also have the advantage of running a little hotter, which helps burn deposits off the spark plug and prevent fouling. Platinum is also resistant to high temperatures, allowing the spark plug to last longer.

Iridium Spark Plugs:

Iridium is six times harder and eight times more potent than platinum. It also has a higher melting point so that iridium spark plugs can withstand higher temperatures. That makes them ideal for high-performance engines and turbocharged or supercharged vehicles.

An iridium plug can last up to 25% longer than a platinum spark plug. Iridium spark plugs are also more expensive than other types. They can cost up to eight dollars each, so keep that in mind when shopping for new spark plugs.

Ending Note:

Before making your final purchase decision, we invite you to schedule a test drive with one of our used cars. 

Our team at Eastern Shore Luxury Cars, serving Theodore, AL, will be happy to answer any questions you may have and help get you behind the wheel of the perfect car for your needs.