Hoovey689

iTrader: (16)

Lies, Damned Lies and Fuel Economy Numbers

"There are three types of lies: lies, damned lies and statistics," goes the old quote variously attributed to Mark Twain, Benjamin Disraeli and other wits. Were they writing today, they'd probably add a fourth: fuel economy numbers.

As regular readers have heard, Hyundai is being sued for allegedly misleading mileage ads. Honda, meanwhile, beat back one Civic Hybrid owners mileage lawsuit upon appeal but also agreed to a settlement covering thousands of others who didn't get nearly what the automaker promised.

Without taking sides in these individual cases. it's nonetheless safe to say that mileage claims are controversial at best, and often inaccurate, at least in terms of what real world driving is likely to yield.

"Your mileage may vary" is a disclaimer we've all heard, and certainly there are enough variables that impact what your car, truck or crossover will deliver: such factors as the speed you drive, what altitude the vehicle is operated at, what fuel you use, whether your tires are properly inflated and how many passengers you've got crammed into the backseat. And considering the added bulk too many of us carry around our middles, even that can play a role.

But there's no question that manufacturers clearly want to put the best face possible on their products and, like that speed-talking spokesman for FedEx some years back, fuel economy disclaimers may be overlooked entirely.

The so-called Monroney sticker, the window label found on all new automobiles sold in the States, dates back to 1958 and legislation sponsored by Oklahoma Senator Almer Stillwell Monroney. Fuel economy numbers were added in the 1970s when Congress authorized the Environmental Protection Agency to oversee the new Corporate Average Fuel Economy [CAFE] standard and to begin testing every new vehicle entering the market.

The challenge – then and now – has been to come up with valid test procedures that come anywhere close to replicating real-world conditions. To help individual motorists adapt the numbers to their own driving styles, the EPA went to a three column approach, with city, highway and combined ratings.

In reality, the EPA employs only about 20 staffers – less than 0.1-percent of its staff – at its Ann Arbor, Michigan outpost to run those tests and they process barely 15-percent of all the new vehicles that come to market each year. For the rest, they take the manufacturers at their word, though random testing – much like the more extensive screening travelers occasionally experience at the airport – is intended to keep everyone honest.

For the 200+ vehicles that are subject to actually testing, the federal agency uses a dynamometer, the automotive equivalent of a treadmill. The computer-controlled devices can simulate such factors as road friction and wind resistance – but specially trained staff actually do the "driving," carefully obeying instructions displayed on a computer monitor to ensure uniform speed, acceleration and braking behavior that can be readily duplicated from one vehicle to the next.

The raw data goes through an incredible amount of finessing to account for such things as the use of air conditioning and other accessories. And the EPA has routinely tweaked the results to reflect increased highway speeds and changes in driving patterns.

It's also had to adapt to technological changes, such as the increased use of all-wheel drive and, most recently, the emergence of battery-based powertrains. The numbers you see on the Monroney today reflect big changes that went into effect for the 2008 model year – driven by the fact that early-generation hybrids routinely performed significantly better in EPA testing than on the road – despite what those hyper-milers might tell you.

Those changes over the years add up. Without these corrections, the unadjusted mileage for the typical vehicle sold in the U.S. in June would have been an even 29.0 mpg. The average Monroney sticker was just 23.6, however – though both figures represent a 17-percent increase from when the University of Michigan Transportation Research Institute, or UMTRI, began tracking the data in October 2007.

Anyway, that's how we wind up with the numbers you see. Or should see. But given a choice of promoting a 28 mile per gallon city-cycle figure, a 32 mpg combined number or the highway-rated 40, well, it's probably no surprise that most (read: "all") car companies flaunt the open-road results. (The exception being hybrids, which typically do better in stop-and-go driving that recharges their batteries.)

And that's where the debate that could land Hyundai in hot water comes in. And it's not alone.

"We'd like to advertise the combined numbers because those are the figures closest to what an owner should get day-to-day," said an official with a major Japanese competitor who asked not to be identified by name, "but if we did that we'd be at a competitive disadvantage."

That's also why makers will continue to use whatever the EPA reports even if they know the figure is inflated. In May, California Superior Court Judge Dudley Gray II overturned a small claims court judgment that originally went in favor of Civic Hybrid owner Heather Peters. "Federal regulations control the fuel economy ratings posted on vehicles and advertising claims related to those fuel economy ratings," he wrote in his verdict.

In fact, that is not the correct interpretation of the law, according to the EPA itself. The figures the agency quotes are the maximum a maker can use but it is legally entitled to lower the figures if it believes they are inaccurate.

Fat chance. Unless someone blinks, or the courts or regulators step in, it's likely you'll continue to see automakers focus on the biggest numbers they can get away with using – putting the rest in the smallest print they also can get away with.

http://www.autoblog.com/2012/07/12/l...onomy-numbers/

ArmyofOne

I always figure at LEAST 5mpg lower than the claims when looking at a car. I was pleasantly suprised with my truck, EPA est was 14/19, and I avg 16-17/21-22 usually. That is part of the reason why it is so hard for me to justify going with a smaller pickup or like a 4-runner or GX, I get the same mileage they do (in the case of the GX, better) and I can do a lot more.

Besides the point. I only use the EPA estimates to give me a general idea of what that car is capable of. I understand YMMV, and that real-world results are not always the case. If we were talking a 10mpg difference here, I could see people getting upset, but the Elantra from Hyundai Claims 40mpg hwy, and its real world calculation is more like 36. 4mpg? Really people? My mileage will vary by 4mpg if I push my gas pedal too far down.

spwolf

as I explained in another thread, problem is when you buy car because of best MPG and to find out it doesnt have best mpg.

Case in point - Elantra vs Corolla - 40 MPG vs 34 MPG EPA HWY
In real life, drivers have found that Corolla gets 31 MPG while Elantra gets 30 MPG.

I am sure you get the issue much better now.

Of course, not like Autoblog tries to understand what they are writing about. For instance, Honda law suit was about Honda implementing TSB for the car to improve battery life that lowered MPG compared to the car that customers purchased. It would be as if you purchase car becuase it has 300hp, and then engines start blowing up during warranty period, and Dodge goes in and lowers the output to 200hp so they dont blow up..... get it? :-)

I8ABMR

aren't these estimates done at 55 mph?? Who the hell drives 55 mph..........ever ......

geko29

Well sometimes you have to slow down for a school zone....

(I keed, I keed!)

Lil4X

Reminds me of the guy who bought the spark plugs that would save 20% on gas, ignition wires that would save 10%, carburetor that would save him 35%, a cam that would save 15%, high efficiency intake and exhaust plumbing that would save another 20%, and low rolling-resistance tires that would save another 10%.

He drove two blocks down the street and his gas tank ran over.



G'night folks, I'll be here all week. Don't forget to tip your waitress!

mmarshall

Where the posted limit is in that range and people don't want tickets.

mmarshall

I don't always get EPA numbers in local stop-and-go driving (The D.C. area has SoCal-style traffic, some of the worst in the country). But I usually have no problem getting EPA or even better on open, level Interstates, staying reasonably close to the limits, and with the car relatively lightly loaded. Keeping the A/C off (when feasible) and using just the vent-fan will also add about 2 MPG or so.

hypervish

I can easily beat the EPA ratings on all of my cars. It depends on the mood I'm in, somedays I'll want to be efficient, and get great mpg. Other days, I'll redline every chance I get and obviously not get good fuel economy.

FrankReynoldsCPA

My car does not do the EPA rated MPG.

EPA on the 92 LS400 is 16 city, 21 highway, and 18 combined.

In the city, i can only get 10-12 usually.
On the highway however, I've gotten as high as 27(doing 75 through 160 miles of hills, twists, and turns, passing other vehicles like they were standing still).

bagwell

+1


posted this before ......only 15% of cars are actually tested by the EPA....

Since the late 1970s, the U.S. Environmental Protection Agency has certified the fuel-economy projections of some 450 million new vehicles sold in this country.

The projections are there by law and appear boldly on the window stickers of new vehicles, for example, CITY MPG 16, HIGHWAY MPG 25. They appear authoritatively, almost like a pledge from the federal government, and motorists have put a lot of faith in these numbers.

The EPA figures also determine whether an automaker meets the required fuel-economy averages for a company’s entire vehicle line, so the numbers are a very big deal. As such, you might expect the federal government’s facility to be about the size of, oh, the Department of Agriculture and loaded to the brim with persistent bureaucrats.

While the public mistakenly presumes that the EPA is hard at work conducting complicated tests on every new model of truck, van, car, and SUV, in reality, just 18 of the EPA’s 17,000 employees work in the automobile-testing department in Ann Arbor, Michigan, examining 200 to 250 vehicles a year, or roughly 15 percent of new models. As to that other 85 percent, the EPA takes automakers at their word—without any testing—accepting submitted results as accurate.

Two-thirds of the new vehicles the EPA does test are selected randomly, and the remaining third are done for specific reasons. We’re not sure why a Porsche 911 GT3 was at the lab when we were there—other than to get an up-close look at its sexy, single-lug wheels—but candidates for scrutiny usually involve new technologies, new manufacturers, class fuel-economy champs, or cars that barely avoid a gas-guzzler tax.

We visited the EPA’s nondescript lab for a look at just how these numbers are derived. Located across the street from the University of Michigan’s North Campus and next to a mundane strip mall, the only clue to its importance is the imposing gate that guards the industrial building complex.

What happens inside is enormously complicated. There are endless reams of documents that explain, in detail, every procedure and circumstance, and each comes with its own set of rules. Even the procedure for rounding off the results of the fuel-economy tests to produce what is published on a new-car label is crazily complex. “We have a guy that’s literally made a career out of specializing in rounding,” says the EPA’s Linc Wehrly, manager of “light-duty compliance,” the man in charge of vehicle testing.

So how does the EPA lab work?

Vehicles are tested on dynamometers, or dynos, which are like giant treadmills for cars. The vehicle is held stationary while its wheels spin the dyno’s large rollers. There are just three dynos, and only one of them is a four-wheel-drive unit with sets of rollers for both the front and rear wheels; the two other dynos are spun by only a car’s driven wheels. The four-wheel dyno was added fairly recently; before that, all testing had to be done on two-wheel-drive dynos, which necessitated the additional complexity of disconnecting driveshafts on AWD models so they could be converted to two-wheel drive. (How weird can it get? The EPA created a two-wheel-drive version of the $1.7 million, 1001-hp Bugatti Veyron—the world’s fastest and most outrageous production car—for this purpose, prompting visions of burnouts of nuclear dimension.) When tested this way, additional drag is applied to the dyno to replicate normal operation of the AWD system.

http://www.caranddriver.com/features...-mpg-estimates

xsh0tya

Well played sir!