Back to all

Mileage Headed Downhill? (What Causes Bad Fuel Economy?)

November 2, 2025

Name someone you know who enjoys spending a lot of money on gasoline.  Yeah, me neither. That’s because it costs quite a bit to keep fueling your vehicle.  

One way to save money on gas is to get good fuel economy, and most of today’s vehicles are designed to maximize your mileage.  But you might find you’re filling up more frequently than you used to and are wondering what can cause your fuel economy to tumble.  Here are a few possible reasons your mileage has been headed downhill.

A logical spot to start is in your fuel system.  You may have a faulty fuel injector or an old fuel filter clogged with debris.  Another problem might be oxygen sensors, which measure the air coming into your engine and the emissions going out. An illuminated Check Engine light may be a sign of trouble there. Plus, worn-out spark plugs can reduce your fuel economy. 

Under- inflated, or over-inflated, tires can also be a cause. Make sure they’re all at the same pressure.  When’s the last time you changed your engine air filter? One that’s clogged and dirty can rob you of better fuel economy. Another bandit is a dirty, leaky, or clogged exhaust system, so have it checked out by a pro.

Finally, how you drive can also mean wasted gasoline. Jackrabbit starts and speeding use more fuel than smoother acceleration.  And if you often sit there with your engine idling while you’re waiting somewhere, you’re throwing fuel away.  Just turn the ignition off.

Try out some of these fuel-conserving habits and they’ll pay off for you in the long-run.

Tuffy Ocala
2105 Southwest College Road
Ocala, Florida 34471
(352) 690-6111

More articles from Tuffy Ocala

Why Maintaining Your Windshield Wipers and Washers Matters (Windshield Wiper and Washer Inspection)

February 1, 2026

What do mud, bird droppings and frost all have in common? When theyre covering your windshield, they can temporarily obscure your view of the road, leaving you driving blind. And when you cant see the road clearly ahead of you, it can be really scary. Thats one of the reasons its important to m... More

You Are the Fluid Detective! (Leaking Fluids)

January 25, 2026

When you see some liquid sitting underneath your vehicle, your mind starts churning. Is that normal? Is that something serious, or did I just spill my drink? Heres a quick list of what those fluids look, smell and feel like, as well as what they might be. No, we dont recommend you taste them to ... More

Before You Buy a Used Vehicle (Car Inspection before Buying a Used Vehicle)

January 18, 2026

Before You Buy a Used Vehicle (Car Inspection before Buying a Used Vehicle) Perhaps this sounds familiar. Your vehicle seems like its been around forever, and youve decided its time to move on. But when you check the price of new vehicles, the sky-high price tags have you considering a nice, pre... More