Not getting the mileage you used to? If your fuel economy has taken a noticeable hit, it's usually not just a fluke. From worn-out parts to simple habits, there are several reasons your vehicle might be burning more fuel than it should. Figuring out the cause can help you save money at the pump and avoid unnecessary wear on your engine. We’ll cover eight of the most common causes and what they mean for your car.
1. Incorrect Tire Pressure
Tire pressure plays a bigger role in fuel efficiency than most people realize. When your tires are underinflated, they create more rolling resistance, making your engine work harder to move the vehicle. Even a few PSI below the recommended level can reduce your miles per gallon noticeably. It’s a good idea to check your tire pressure monthly and adjust it based on the manufacturer’s specifications—usually found on a label inside the driver’s door.
2. Worn Spark Plugs
Your engine’s combustion process depends on a strong, consistent spark. As spark plugs age, they can misfire or fail to ignite the air-fuel mixture efficiently, leading to reduced performance and increased fuel usage. If your plugs haven’t been replaced in a while or you’ve noticed sluggish acceleration, they could be part of the problem. A quick tune-up often restores both power and economy.
3. Dirty Air Filter
When your engine can’t breathe properly due to a clogged air filter, it compensates by burning more fuel. This is especially true in stop-and-go traffic or under load, like when towing or climbing hills. Replacing the air filter is simple and inexpensive, and it can make an immediate difference in fuel efficiency and engine responsiveness.
4. Low-Quality or Wrong Type of Oil
Using the incorrect grade of oil for your engine can increase internal friction and reduce fuel economy. High-mileage or synthetic oils are often recommended for older vehicles, while newer cars may require low-viscosity blends for optimal performance. If you're overdue for an oil change or using a generic oil type, your engine may not be running as efficiently as it could be.
5. Failing Oxygen Sensor
Your vehicle's oxygen sensors help regulate the air-fuel ratio. When they fail, the engine may run rich, using more fuel than necessary. This issue often triggers the check engine light and is common in high-mileage vehicles. Replacing a bad sensor can improve fuel economy by as much as 15–20%, depending on how long the issue has gone undiagnosed.
6. Aggressive Driving Habits
Quick acceleration, speeding, and frequent hard braking all lead to higher fuel consumption. Even something as simple as keeping your RPMs lower and coasting more often can make a noticeable difference. Adopting smoother driving habits doesn’t just save fuel—it reduces wear on your brakes and tires too.
7. Excess Weight or Drag
Carrying heavy cargo or keeping roof racks, bike mounts, or storage containers installed full-time increases aerodynamic drag and overall weight. That puts more strain on your engine, especially at highway speeds. Lightening your load and removing unnecessary accessories can help you gain a few extra miles per gallon.
8. Fuel System Problems
Clogged fuel injectors, a dirty fuel filter, or a weak fuel pump can all lead to inefficient fuel delivery. You might not feel a performance drop right away, but over time, your engine will struggle to maintain the correct mixture, especially under load. Fuel system cleaning or replacement of key components can bring fuel usage back under control.
Sunny Service Center – Helping Margate City Drivers Save at the Pump
Tired of spending more at the gas station? At Sunny Service Center in Margate City, NJ, we fix the real reasons behind poor fuel economy. Whether it’s something simple like tire pressure or a deeper engine or fuel system issue, our technicians will help restore efficiency and performance. Let us help you make every drop count—schedule your fuel efficiency check today.