Miles per gallon (MPG) is typically something we don’t mind much of until we notice a dramatic change in the amount of miles we can get on a tank as it usually impacts our bank balance.

Sometimes when our MPG changes dramatically, this can be an indicator that something is going on mechanically with our car. That is why it is important to be mindful of it as you might be able to diagnosis a problem before it leaves you stranded on the side of the rode.

So what can your MPG tell you? Below are four things that could be going on mechanically with your car:

  • Spark plugs going bad

Spark plugs are typically meant to last around 10 to 20,000 miles for copper plugs and 50 to 60,000 miles for iridium or platinum plugs. If you haven’t had your spark plugs changed since you bought your car, this would be an easy .

  • Low tire pressure

One of the easiest things to check on your car is your tire pressure. You can buy at any retail store a tire pressure gauge which simply pushes onto the stem of your tire and reads out your pressure. Comparing your cold tire pressure (i.e. when your car hasn’t been driven in a couple of hours) to the tire pressure markings on the inside of your drive side door can show whether or not you are running too high or low of air pressure. Running below the recommended air pressure is not only bad for your tires but also will negatively impact your MPG.

  • Clogged air intake filters

Air filters on your car intake need replacing every 15 to 30,000 miles depending on your vehicle. Having an air filter that is near the end of it’s life, or well past the recommended interval can result in as much as a 20% reduction in your MPG.

  • Bad fuel injectors

A bad fuel injector could be the culprit for a reduction in MPG as it is the component directly responsible for delivering the fuel into your engine’s cylinder where power is made. If the fuel injector is leaking or clogged, this too could negatively affect your MPG. Typically, fuel injectors need to be replaced every 50 to 100,000 miles depending on the vehicle and type of fuel injector.

Lastly, your sudden change of MPG could also be a result of more aggressive driving or sudden increase or reliance on A/C. But those are more problems to do with you then an issue cropping up mechanically in your car ;).

Share with us in the comment section below what tips you’d recommend for increasing your MPG!

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