Facts About Vehicle Fuel Economy
NDSU dispels fuel mileage misconceptions.
People looking for ways to reduce their vehicle's fuel consumption to save money may have some misconceptions about fuel economy.
"One of those misconceptions is that a vehicle has to be a compact car to get good mileage," says Carl Pedersen, North Dakota State University (NDSU) Extension Service energy educator. "But that's not the case. You can get great fuel economy in standard-sized cars with newer technologies such as diesel engines, hybrid drive trains and advanced transmissions. In fact, the most fuel-efficient car for the 2010 model year was a midsized car."
The U.S. Department of Energy and Environmental Protection Agency have teamed up to provide information about fuel use for people who plan to buy a vehicle or want to make the one they have more fuel-efficient. That information is available on a website at http://www.fueleconomy.gov.
Here are some other misconceptions about fuel economy:
- Misconception: Manual transmissions use less fuel. Thanks to computer-controlled shifting, vehicles with automatic transmissions can get about the same or even better mileage than similar models with a standard transmission.
- Misconception: Vehicles need to warm up before being driven. Actually, a vehicle that is idling is getting zero miles per gallon, so minimizing idling can improve fuel economy. While allowing vehicles to warm up in northern climates may make the ride more comfortable, you can drive almost immediately after startup without being concerned about engine or drive train damage. However, you should allow the engine to reach a normal operating temperature before doing any severe driving.
- Misconception: Fuel economy drops as a car ages. Fuel economy varies with the number of miles you drive per year. However, according to the EPA, a vehicle's mileage will improve for the first few years and will not decline much as long as the vehicle is maintained properly.
- Misconception: Dirty air filters reduce fuel economy. Recent studies have shown that fuel-injected engines can compensate for dirty air filters without reducing fuel economy. Dirty air filters may affect a vehicle's performance but should not affect the mileage until the air filter is so clogged that the vehicle has noticeable performance issues.
- Misconception: Gas additives and devices save fuel. Of all the additives and devices the EPA has tested, none has improved fuel economy significantly, and some may harm a vehicle. The EPA has tested more than 100 alleged fuel-saving devices and found none that improves mileage more than a minor amount.
- Misconception: Starting a vehicle uses more fuel than leaving it idling. The fuel-injection systems used in vehicles today will start a vehicle very efficiently. If you are going to be idle for more than a minute or two, you should shut the vehicle off.
- Misconception: Premium fuel is more efficient. Unless your owner's manual specifically calls for premium fuel or your vehicle will not run smoothly on regular gas, using premium most likely will not increase fuel economy.
"You need to remember that fuel efficiency depends on a number of factors, so these tips may not work in every case," Pedersen says.
"The best way to reduce fuel consumption is simply not to drive," he adds. "Walking, riding a bike or carpooling are all great ways to save fuel and money. If you have to drive, try purchasing a vehicle that is fuel-efficient."
The website at http://www.fueleconomy.gov can help you compare cars' efficiency ratings.
For more information about other ways to cut your energy costs, visit NDSU's energy website at http://www.ag.ndsu.edu/energy/ .
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