True or False: The Fuel Economy Myths Quiz


By: Staff

5 Min Quiz

Image: refer to hsw

About This Quiz

Fuel is a huge expense for many Americans, with the average driver shelling out just under $2,000 a year on gas, according to the Bureau of Labor Statistics. People with long commutes or higher costs of living can spend much more.

Gas guzzling also has an impact on the environment, spewing pollutants into the air that affect air and water quality, which eventually harms not only people but also plants and wildlife.

The good news is that there are dozens of steps you can take to improve fuel economy, protect the planet and keep more cash in your wallet. The bad news? A surprising number of widely known fuel saving tips have no basis in fact. As cars and technology have changed over the decades, people have kept on believing the same old fuel economy myths, rather than switching to strategies that actually make a difference.

That means you could be sweating it out in a broiling car because you're convinced that using the AC or rolling down the windows will blow your gas budget. It might also mean you're missing out on easy opportunities to cut fuel costs, like maintaining the right tire pressure, in favor of things that actually have zero impact on gas mileage.

Think you have what it takes to separate fact from fiction? Take our fuel economy myths quiz to find out!

True or false: Smaller cars always get better gas mileage than larger ones.

Thanks to continuous improvements in auto technology, smaller cars aren't always the most efficient. In fact, half of the cars on the Environmental Protection Agency's (EPA) list of most efficient vehicles for 2016 are midsize or larger.


True or false: Cars with an automatic transmission will never be as efficient as cars with a manual transmission.

In modern vehicles, cars with an automatic transmission often have the same or better mileage as the same model with manual transmission.


True or false: Idling your vehicle can cost you 1 to 2 cents per minute.

Idling costs between 1 and 2 cents per minute in gas and can use one-third to one-half gallon of gas per hour.


True or false: Aggressive driving can significantly reduce fuel efficiency.

Aggressive driving can reduce gas mileage by 5 percent on city roads and as much as 33 percent on the highway.


True or false: Speeds above 50 miles per hour (80 kilometers per hour) significantly reduce fuel efficiency.

Every 5 miles per hour over 50 miles per hour adds about 12 cents to each gallon of gas you buy.


True or false: It's always more efficient to let your vehicle idle than to stop it and restart it.

Starting a modern vehicle uses as much gas as 10 seconds of idling, so it almost always makes sense to turn your vehicle off rather than leave it on while you're waiting.


True or false: Carrying cargo on top of your car cuts fuel economy by 2 to 8 percent.

A top-mounted cargo container cuts fuel efficiency by 2 to 8 percent in the city and as much as 25 percent on the highway.


True or false: Removing 100 pounds (45 kilograms) of cargo from your vehicle can improve fuel economy by 1 percent.

Extra weight wastes gas, and every 100 pounds you carry can reduce gas mileage by 1 percent.


True or false: Using cruise control on the highway boosts fuel efficiency.

By helping you maintain a constant speed, cruise control saves you gas and money when you're driving on the highway.


True or false: A 10-year-old car will almost always get worse mileage than one that's newer.

If you properly maintain your vehicle, you shouldn't expect to find any significant decrease in fuel economy, even after 10 to 15 years of ownership.


True or false: Changing a dirty air filter increases fuel efficiency.

In modern vehicles, replacing a dirty air filter may improve vehicle performance, but it's unlikely to improve fuel economy all that much.


True or false: Premium fuel offers no advantages to most drivers in terms of fuel economy.

While you should always use premium if your car requires it (check the manual), premium fuel does not improve mileage in the average vehicle.


True or false: Ethanol-blended gasoline increases fuel efficiency.

A 10-percent ethanol blend decreases fuel efficiency by around 3 percent thanks to the lower energy density of the ethanol.


True or false: Driver feedback devices can improve your driving skills but don't really help fuel efficiency.

The average driver will naturally improve fuel economy by 3 percent when using a driver feedback device, while a person who uses this device primarily to improve mileage can boost efficiency by as much as 10 percent.


True or false: Rear-mounted cargo containers are even worse for fuel economy than roof-mounted containers.

A rear-mounted cargo container only reduces mileage by 1 to 2 percent in the city and 1 to 5 percent on the highway.


True or false: Replacing a faulty oxygen sensor can improve mileage by as much as 40 percent.

Replacing a damaged oxygen sensor — a relatively simple fix — can improve fuel economy by as much as 40 percent.


True or false: Correcting air pressure problems in your tires won't really impact fuel efficiency.

Making sure your tires are properly inflated can boost fuel economy by 3.3 percent on average.


True or false: Even a single pound-force per square inch drop in pressure can impact how much gas your car uses.

Every 1 pound-force per square inch (6,895 pascal) decrease in tire pressure equates to around a 0.03 percent decline in fuel economy.


True or false: Motor oil has little impact on fuel economy.

Using the recommended motor oil for your vehicle improves fuel economy by an average of 1 to 2 percent -— that's like saving 2 to 3 cents per gallon.


True or false: Combining trips saves fuel, especially when it's cold outside.

Several short trips can actually consume more fuel than one longer trip covering the same total distance. This is especially true if your vehicle is cold when you start it.


True or false: Cold weather increases gas mileage.

Fuel economy decreases by 12 percent when the temperature drops from 70 degrees Fahrenheit (21 degrees Celsius) to 20 degrees Fahrenheit.


True or false: The longer you allow your vehicle to warm up, the better your fuel efficiency will be.

The best way to warm up a car is to drive it. Allowing the car to sit idle simply wastes gas.


True or false: You can boost fuel efficiency by 4 percent by tuning up a noticeably out-of-tune vehicle.

If your vehicle has some problems or fails an emissions test, you can expect to boost fuel efficiency by 4 percent with a proper tuneup.


True or false: Air conditioning can reduce fuel efficiency by 25 percent.

Using your air conditioner can reduce fuel efficiency by as much as 25 percent during the peak of summer.


True or false: Rolling your windows down doesn't impact fuel economy when driving on the highway.

Rolling your windows down has a dramatic effect on fuel economy on the highway. To maximize efficiency, use your air conditioning on the highway and roll your windows down to cool off while driving in the city.


True or false: Fill your car early in the morning during the summer to get the most bang for your buck.

Because most gas stations store gas underground, the idea that you'll get more gas for your money in the cooler morning hours is no more than a myth.


True or false: Gas-saving products and additives can actually improve fuel economy.

An EPA review of more than 100 devices and products that promise to improve fuel economy found that none actually have any significant impact on mileage.


True or false: Lowering the tailgate on your pickup worsens fuel economy.

In a Consumer Reports test, lowering the tailgate or adding a tonneau cover to a pickup actually made fuel economy worse, not better.


True or false: Fuel economy estimates are a guarantee of performance.

Fuel economy tests and ratings don't always reflect real-world performance and are designed as a way to compare the relative fuel efficiency of different vehicles.


True or false: Around 5 percent of all consumer spending goes to gasoline.

The average U.S. household spends around 5 percent of their money on gas, which breaks down to almost $2,000 per household in 2015.


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