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Among the many things that require routine maintenance on our vehicles are spark plugs.   If your mechanic says you need new spark plugs and you don’t understand why, the explanation of their importance may sound like a second language.

Maybe you’d like to speak the language of your mechanic and have a sense of what spark plugs are and why they need to be in good working order.  So, if you’re of the mindset that it can never hurt to learn a little about car maintenance, here’s your spark plug tutorial.

Why spark plugs are important.
Your car won’t start without them.

Why your car won’t start without spark plugs.
Here’s how the process works. A spark plug receives an electrical signal from the ignition coil. Spark plugs were well named because a spark is created, and that spark ignites the air-fuel mixture inside the combustion chamber which allows the engine to turn and run. Basically, without spark plugs, your car is a large paperweight.

The spark plugs should be in good working order.
Now, they don’t have to be, for your car to drive. If you have spark plugs that are wearing out, but they still work, your car may end up moving, but you may find that it takes a little longer to accelerate on the gas, and in general, your car may not get as much mileage. With old or worn out spark plugs, the combustion in the cylinders is not as efficient as what the engine was designed to do. This allows unburned fuel into the exhaust. Overtime, this unburnt fuel has a adverse effect on the life of your catalytic converter and exhaust gas sensors. If you have ever replaced a catalytic converter, or two, you know you don’t want those to be adversely affected. It also means you’re driving on borrowed time. If your spark plugs are weakening, it isn’t as if they’re going to get stronger on their own. Eventually, you will be driving and the Check Engine Light will come on. This could be due to a number of things that worn spark plugs can affect, most of which cost far more than a set of plugs. Worse case you’re going to amble over to your parked car and turn the ignition and nothing will happen.

It’s natural for spark plugs to be replaced every so often.
You can take the best care of your car and you’ll still need to get them replaced. Spark plugs are generally installed every 20,000 – 40,000 miles. So, if you drive a lot, you may end up replacing them every couple years or a little less frequently if you’re not putting a lot of miles on your car.

Are there other benefits to having new spark plugs?

  • Your car’s overall performance should improve. If you were operating on weak spark plugs, and you always had to press your foot to the gas for longer than seemed normal, that should stop now.
  • You’ll fill up at the tank less. Your fuel economy should improve.
  • Less air pollution. Fewer emissions will come out of your car when your spark plugs are working properly.
  • No crazy ignition sounds. You’ll turn on the ignition and away you go – instead of having a car that has a hard time starting or jerks around as you try to leave the driveway or a parking lot.

If you want to impress your friends with your spark plug knowledge…

Copper spark plugs tend to have the shortest life span. Platinum spark plugs are better than copper but also considered to be somewhat inferior to the best spark plugs, which are made of iridium spark plugs, which, yes, cost more but tend to last the longest. Helpful rule of thumb: the stronger the material, the more long-lasting the spark plug. Also, if you bought the car new, the brand and style of plugs that are in the car are a good starting point on what you should have placed back in the car. Changing spark plugs to what is on sale or to what is the latest promoted style could cause your engine to perform poorly. For example, a spark plug that works best in a Honda Accord is not the same brand or style as one for a Ford F-150.

Still, unsure as to which type of spark plug is the best one for your vehicle? Be sure to check your owner’s manual or consult a technician at your local Milex Complete Auto Care / Mr. Transmission.

But the next time you bring your car into a Milex Complete Auto Care / Mr. Transmission for a question about spark plugs, hopefully you’ll feel like you’re speaking their language.


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