Do feel like your fuel expenses have skyrocketed lately? If the prices aren’t rising at the pump, chances are faulty vehicle parts are to blame. When it comes to declining fuel economy, there are many possible causes, and fortunately, most of the issues that can cause your gas mileage to plummet are easily fixable.


Some of these problems are so simple you probably take care of them yourself, while others will require the expertise of a certified auto mechanic. Read on to learn about the most common causes of poor gas mileage and how you can fix it. 


Bad Fuel Injectors

Faulty or dirty fuel injectors can’t deliver sufficient fuel to your vehicle’s engine, which means it won’t run efficiently. Ultimately, when your engine isn’t as efficient as it could be, it’ll eat up more fuel than it should.


To find out if bad fuel injectors are the culprit behind your poor fuel economy, take your vehicle to an auto mechanic for a checkup. You can try pouring a bottle of fuel injector cleaner into your gas tank to see if it helps, but those products are really meant for regular use. When you get your injectors replaced, using a cleaner on a routine basis can help keep your gas mileage where it’s supposed to be.   


Underinflated Tires

If your tires aren’t inflated to the proper PSI, your fuel economy will inevitably suffer. Every vehicle has a specific PSI at which the tires are supposed to stay. Underinflating leads to lower gas mileage while overinflating can cause uneven tire wear, poor traction, and reduced tire performance. 


If you're unsure of the proper PSI for your vehicle’s tires, take a look at the inside of your driver’s side door panel. There, you should see a sticker that lists the appropriate PSI for your tires; your manual may also contain this information. Once you know what the right PSI is, use a tire gauge to test yours and inflate them to the appropriate air pressure. 


If your tires are old, opting for replacement tires will not only improve your fuel economy but also your safety on the road.


Bad Air Filter or Oxygen Sensor

A bad oxygen sensor or air filter cannot allow enough clean air to reach the engine, which results in an improper air-to-fuel ratio. When the balance of air to fuel is off, the engine cannot burn fuel efficiently, so it’ll consume more gas to get you where you need to go.


Air filters are inexpensive and easy to replace, so this may be a job you can do on your own. However, if you’re unsure of how to find the right air filter or replace your existing one, take your vehicle to an auto mechanic to make sure it’s done right.


If you think you might need a new oxygen sensor, a qualified auto mechanic can test yours and let you know if that’s the culprit. Your dash lights may also indicate the need for a new O2 sensor.


Defective Spark Plugs

Old or faulty spark plugs negatively affect fuel combustion inside your vehicle’s engine. Over time, the heat and pressure inside the engine cause the gaps between the plugs to widen, leading to inefficient functioning.


Spark plugs should be changed according to your vehicle’s recommended maintenance schedule — usually every 30,000 to 90,000 miles. If yours haven’t been changed in some time, they may be to blame for your poor gas mileage.


Driving Habits

If you’re an aggressive driver, you’re probably decreasing your fuel economy without knowing it. Accelerating rapidly or revving your engine both waste a considerable amount of fuel. If you’re guilty of doing those things, there’s a good chance your foot is the culprit behind your poor gas mileage.


If you keep up with routine vehicle maintenance and your fuel economy is poor, try changing your driving habits. You might be surprised at how much fuel you can save just by taking it easy on the road.


Talk to An Auto Mechanic About Poor Fuel Economy Today

If your vehicle is getting bad gas mileage and you’re not sure why, get in touch with our team at AA Auto Tech in Hastings, MN. Since 1979, we’ve specialized in comprehensive auto repair and maintenance for vehicle owners throughout the Twin Cities, and when you need a mechanic you can trust, we’re here for you too.


To learn more or schedule an appointment, give us a call today at 651-437-2218 or send us a message, and we’ll be in touch.