What You Need to Know About Spark Plugs

What You Need to Know About Spark Plugs


If you’ve ever spent any time around automobiles, you’ve likely heard the phrase “spark plug,” mentioned. No, this isn’t referring to a person with a fiesty attitude, it is actually a very integral piece of an automobile’s internal combustion system, that helps your vehicle start – and without one, it won’t start at all. While that is the most basic function of a spark plug, there is actually much more to know about how it works, its life span and when you know it is time for a replacement.

What is a Spark Plug?

A spark plug dates back to the mid 1800s, and has been credited to several inventors who created various versions of “spark ignition” in an internal combustion engine. At its most basic level, a spark plug is defined as “a device for firing the explosive mixture in an internal combustion engine.”

Spark plugs are mainly produced in three different materials: copper, platinum, and iridium. While the copper spark plugs are often less expensive than their stronger counterparts, the stronger metals provide a longer life span.

How does a Spark Plug Work?

When an ignition key inside a vehicle is turned, the spark plug sends an electrical signal through the ignition coil. Spark plugs were named because when that electrical spark is created, it ignites the air-fuel mixture inside the combustion engine – and the engine begins running.

In order to “fire” an engine and get it started, a spark plug is a necessary component of your vehicle. The tiny jolt of electricity provided by a spark plug is enough to get the pistons in an engine moving, burning fuel, and getting your vehicle on the road.  

Why and How Do Spark Plugs Wear Down?

Given their necessity in the starting of a vehicle, a spark plug is continually in use, and can wear down over time. The wear and tear levels of a spark plug can depend a lot on the material that the spark plug is made from – stronger materials last longer -- but there are two main exterior causes.

First, the “gap” that the spark has to cross could broaden over time, making it more difficult for the spark to ignite the air-fuel mixture the proper manner. If the gap is too far apart, the engine may misfire. The gap widens as due to a number of causes, include engine debris, excessive wear and tear, and extreme heat that is faced in the internal combustion chamber.

Another cause of wear and tear for a spark club is caused by deposits forming on the exterior of a spark plug. These deposits can lead to pre-ignition of the fuel, and a variable, if not undependable, supply of energy for your vehicle.

Spark plugs do not have to be at 100 percent in order for your vehicle to start. If you have spark plugs that are wearing out, but they still barely work, your car may end up moving, but you may not start as easily or get as much gas mileage as you’re used to. It also means you’re driving on borrowed time, and it may be time to replace your spark plug.

When is it Time to Replace Your Spark Plug?

The average lifespan of a spark plug is approximately 30,000 miles. This is obviously dependent on the level of vehicle use and spark plug material, but if you are experiencing any of the following symptoms of your vehicle, it might be time to have your spark plug and engine inspected.

  • You have any difficulty starting your car.
  • If your engine makes odd noises while idling.
  • Your average miles per gallon or fuel efficiency are lower than usual.
  • Your engine misfires, surges, or “hesitates.”
  • Your vehicle does not accellerate at the rate you’re acustomed to.

How Do I Replace A Spark Plug?

Click here to find your nearest Milex Complete Auto care,

If it has been a while since you had your spark plugs replaced or if your car is experiencing any of these problems, please visity your nearest Milex Complete Auto Care and one of our mechanics will take a look and have you back on the road in no time!


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