Your fuel mileage may vary — And here's why
Aggressive, jerky driving slurps extra fuel — up to 33% more on the highway and 5% more in town.
On a recent road trip, the 2012 Hyundai Elantra I was testing averaged 34 miles per gallon in mostly highway driving. That's pretty good — but not as good as you might expect. The Environmental Protection Agency's highway-mileage figure for the Elantra is 40 mpg. A few months earlier, Hyundai had come under fire from Consumer Watchdog, which disputed the Elantra's fuel-economy numbers after Hyundai ran a high-profile ad campaign touting them. Hyundai says it stands behind its numbers, and the EPA has since verified them.
How the tests work.
This dispute over fuel economy is only one example of how the EPA's mileage numbers often don't mirror many drivers' results. The main reason for the discrepancies, as Hyundai Motor America CEO John Krafcik points out, is driver behavior. Jeff Bartlett, of the Consumer Reports auto team, says the EPA numbers are a good guide, but "only the guy in the lab is going to get those exact numbers."
Here's how the tests work. Cars are placed on a dynamometer (a treadmill of sorts) and put through the paces of five testing cycles. In years past, the EPA's tests measured mileage under standard city and highway conditions. But the agency revised its tests for the 2008 model year. So now there are tests that reflect faster speeds (up to 80 miles per hour) and acceleration, air-conditioner use, and colder outside temperatures. The test cycles cover 44 total miles altogether and take a little over an hour and a half. "This is more than sufficient to determine fuel-economy estimates," says an EPA spokeswoman. Manufacturers test their own vehicles and report their results to the EPA, which reviews the reports and verifies 10% to 15% of them. Because the EPA tests are simulated, real-world fuel economy can be better or worse than the agency's numbers. That is supported by the EPA's Web site, FuelEconomy.gov, which allows drivers to report their numbers.
Driving better results.
Where and how you drive are the keys to your fuel economy. The EPA's annual fuel-cost numbers assume you drive 15,000 miles a year, 55% of them in the city and 45% on the highway. If you live in a rural area, you probably cover more miles at highway speeds; in an urban area, much less.
Although my road trip in the Elantra was mostly on the highway, it takes some city driving to get out of the Washington, D.C., area. Focusing solely on the highway figures, Popular Mechanics ran its own tests on the Elantra and the Ford Focus SFE, which also claims 40 mpg. In both cases, the cars "easily cleared 40 mpg, and astonishingly approached 50," it stated in an online story in February.
Terrain and weather also affect mileage. If you live in the South, for example, you are likely to get better mileage on the region's flat roads, but you may also use your air conditioner more often. Running the A/C on the highest setting can reduce fuel economy by 5% to 25%. Likewise, drivers in the Northeast and Northwest have to contend with cold winters and hilly roads.
Your driving style makes a difference, too. Aggressive, jerky driving slurps extra fuel — up to 33% more on the highway and 5% more in town. If you typically emulate Speed Racer, consider that every five miles an hour over 60 mph is like paying 31 cents more for gas. To maximize fuel economy, drive smoothly and don't speed.
Automakers often hype highway mileage in their advertising, and window stickers boldly list separate city and highway numbers — but minimize the combined fuel-economy number you are likely to get in mixed city and highway driving. For the 2013 model year, the EPA is introducing new window stickers that will emphasize the combined mileage number and give a range of fuel-economy figures for categories of vehicles. That way you can compare apples to apples.
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Ethanol lowers the MPG of gas dramatically! I get 20% better mileage when I burn ethanol free fuel. How does burning more gas to go the same distance "stretch the supply? It doesn't. The only thing getting stretched are the oilmen's and corn growers pocketbooks. Also the process of turning corn into fuel produces the same amount of fuel that is consumed making it for zero net gain.... This is good??
The politicians relatives are getting richer while we get less for our money. Throw the bums out!
So much talk about not driving aggressively to save gas. Are they being serious? If you drive like a fart, going 30 miles an hour in a 45, it will take you at least 50% longer to get some place, meaning you are running your engine 50% more.. and waiting for more red lights, and idling more and more.
The secret to saving gas is not not having to come to a dead stop every 1 block to wait for a red light. If the US is serious about saving gas, they should make better efforts to sync traffic lights like many European countries do.
Here's how the tests work. Cars are placed on a dynamometer (a treadmill of sorts)
No wonder the results are always high... No factor for wind resistance.
Why not just drive the vehicle and crunch the numbers? Because then we would see the true mileage instead of what the manufactures want us to believe.
"EPA estimated mileage"? Where do you think the EPA gets their estimates? Yep, the car manufacturers. The EPA gets their own 10% to 15% review of estimates by running a car for 44 miles on a Dynamometer? I'm sure that tells a lot. Man, what a waste of tax payer dollars this agency is.
I had a 92 Pontiac Grand Am with the little 4 cyl. engine. In California, I got about 18 city/ 24 highway. Headed to Oklahoma, by the time I left Albuquerque, I was getting 40 MPG running 70 MPH with the air conditioner on full blast. Ran in excess of 40 MPG until I got back to California. My opinion: California puts crap in its gas to "help" the environment. Of course you cut pollutants per gallon, but you burn twice as much gas. DUH!
Over 20 years ago my brother, a top-rated mechanic for an auto dealership, told me NOT to take the mileage figures seriously. HIS CONTENTION was to use the EPA figures for comparing the mileage differences between model X versus model Y.
In other words, if a person wants to know if there is any difference with fuel mileage between a Chevy Suburban, with combined EPA figure of 17 mpg, versus a Chevy Sonic, of around 26 combined EPA mileage . . . at least the consumer has a measurement to know that the Sonic MAY get 35 percent better mileage over the Suburban.
But I've never bought into what the advertised figures as being what the real-world fuel mileages are.
I'm disappointed that the compact cars, of 2012, are not doing better than from 20 years ago. I have a 1992 Honda Civic that still does average fuel mileage numbers nearly as well as the new models.
And the claims about California gasoline, with its lower mileage, is true. I live in Nevada, that gets its fuel from California, and I make many trips in Utah, which refines locally. The Utah gasoline ALWAYS gives me better fuel mileage. And that should not be so since the Utah driving is at a higher altitude than in Nevada.