Hyundai may be inflating MPG figures - UPDATE: busted by EPA
 

Here's a good article on the discrepency between posted MPG figures and real life results from owners of the Elantra.

UPDATE: Hyundai Responds to Consumer Watchdog's Elantra Fuel Economy Complaints - WOT on Motor Trend

...GM needs to do the same thing (damage control) about the MPG differences for the automatic Cruzes between EPA and real-world customers!

...the "manual" tranny Cruze owners seem to beat their EPA numbers easily, while the "automatic" Cruze owners seldom even meet their EPA numbers.

Here is a recent analysis that I performed based on comparing EPA numbers to fuelly.com numbers for cars rated at about 40 mpg.

http://www.crzforum.com/forum/member...d-december.png

Hyundai way underperforms their EPA numbers; Honda seems to outperform.

I beat EPA (in 11' Sonata) before learning to drive more efficient.
EPA
City-24
Highway-35
Combined-28

First ten tanks averaged 31.2 or so, and the last ten is around 37.

Have not had a combined tank under 35 in a long time now, and I probably can do better.

Do you do EOC or just coast with engine on and drive smarter? Beucase their test would have to be done as a average driver would drive.

I can't see the EPA being involved in some kind of conspiracy here.

However, I can see how a vehicle manufacturer could design a vehicle's
propulsion equipment/algorithms such that the vehicle achieves overly
optimistic, read not easily reproducible in the real world, MPGs on the EPA
test cycle.

I think that most folks either don't know or forget that the MPG numbers
coming out of the EPA testing are intended for direct comparison purposes.

The EPA numbers are an estimate based on an arbitrary test cycle. They are
not a guarantee of anything meaningful. Given the infinite different driving
conditions and driver capabilities/commitment, the EPA estimate does not
necessarily predict any particular driver's MPGs. With a large enough random
sample, drivers of vehicles with a 30 MPG EPA estimate will most likely see
greater MPGs than drivers of vehicles with a 20 MPG estimate.

If the EPA estimate is taken as an average estimate, half the drivers of a
particular car will exceed it, and the other half wont.

Which half would you expect to self-select to raise a ruckus?

E-on-C and drive smarter, but the car could do much better with some simple reprogramming based on what the UG tells me. 2 small changes would probably net 3-4 mpg better.

But they are not comparable! If Honda, say, under reports MPGs and Hyundai, say, ultra-tunes their engine to achieve higher EPA MPGs then the comparison is between apples and oranges. People expect to use EPA numbers to compare cars but if automakers are gaming the EPA numbers, then there is no basis for comparison.

If you are interested in MPGs then the only relevant comparison is from real-world MPG numbers. Those numbers are hard to come by; but less so with websites 'crowd sourcing' MPG numbers.

Of the cars that are listed, the Hyundais do tend to be a bit "sportier," and I wouldn't be surprised if some of those low mileage numbers are caused by the owners' driving habits.

Self reported BS. All this tells us is which driver's are the biggest liars. I'll take the EPA test numbers over a bunch of self reporting nitwits any day.

The cars listed in the chart were 2011 cars claiming to get 40 mpg (plus a few 2012 cars, plus a couple cars near 40 mpg) based on a Motor Trend article. Not sporty or economy based.

You'd think that people reporting their fueling data would be more inclined to drive with an 'eye' on the accelerator pedal. Thus, numbers at fuelly.com, for example, should actually be better then the total driving population mpg numbers.

Yet the Prius is getting worse mileage.

With most of the members of this forum getting >20% better than EPA estimated figures, I'm guessing that those drivers on fuelly.com aren't driving with enough of an "eye" for mileage.

Also, I agree that people who report on fuelly.com are interested in fuel economy, and they are the same people who would be drawn to fuel efficient cars (like the Hyundai line up). However, neither of those facts mean that those drivers are actually knowledgeable of hypermiling techniques.

And by "sporty," I was simply referring to the fact that the Hyundai have better performance numbers than their Toyota and Honda counterparts. Having an increased power-to-weight ratio often leads to more aggressive (and consequently less fuel efficient) driving.

I know that my Honda Hybrid is a throttle by wire, so the computer actually modulates the throttle linkage.

I wonder how many on the list are throttle by wire? Could explain the Honda difference.

As impressed as i am about 69MPG in a Ferrari Enzo and 38MPG in a DeLorean i'm a bit skeptical of their stats :P

One must also consider the number of people with very short commutes who will never reach EPA numbers. There are many Prius owners who are stuck in the low 40s because their commute is under 5 miles. That short of a commute would put an Elantra in the 20s. There are just too many variables. :)

^^^ Would you expect Honda owners to have different, average 'variables' compared to Elantra and Prius owners? Probably not. So what explains that a few Hondas do consistently better than EPA numbers and a few Hyundai's do consistently worse?

That's just it. We don't know what the people on Fuelly are doing for their daily driving. Nor do we know if people are just on there entering BS data either too high or too low just to make their model of car look good or bad. It's like having a bunch of mommy bloggers entering BS information because they are being paid by a company. :)

Just look at the histograms and you can see that there are no systematic abuses of the MPG data. Unless you want to postulate that some conspiracy theorist (Honda, Hyundai) have hired all fuelly users for their vehicles and have crafted a realistic histogram at an elevated MPG level (or for Hyundai, at a reduced level).

Also, fuelly.com takes steps to reduce competition - for example, by never comparing or ranking vehicles directly. This is described in their website forum (as a FAQ response).

Yes, abuses can occur. But you'll need more evidence to discount this set of data.

I just looked at a 1999 Maxima on fuelly and it was supposed to be averaging over 30 MPG, so I looked at the stats. One entry has it getting 70 MPG, over 400 miles on just over 6 gallons, while another has it using 15 + gallons and no mileage is entered. That one is total crap. Not sure about the rest but if that is an example then it is useless. Most of the rest are close to 22-23 MPG while my last tank was 28 with my mild hypermiling techniques and local route knowledge. Give me a deserted road and no traffic lights and I could probably put along at 45-50 MPH and get close to 48-40.

Mine are usually very consistent, with winter temps costing some and extreme heat in summer costing some with AC use. The CBR was at low 80s this summer and now it is the low to mid 70s with the colder weather.

As the manufacturers learn to build more efficient vehicles, it will get harder to get high percentages over EPA in mileage, unless you average speeds as very low and your efforts to utilize all hypermiling techniques are dedicated. Lower average speed get you there with less total energy consumed and will always provide much higher mileage.

I have driven our Sorento locally and on the highway for short distances and I can match the EPA figures if I am fairly careful. To get to 35% over in the Maxima is easy, in the Sorento it would be impossible.

In the context of my experience, my Austin Healey Sprite got 32 MPG in 1969. The Maxima got close to the same in 1999 and the Sorento got close to the same in 2011.
The Sprite was 1 liter and about 1200 pounds. The Maxima is 3 liters and just under 3000 pounds. The Sorento is 3800 pounds and 2.4 liters. The Sprite was probably 40 HP and would not go over 84 MPH. The Maxima and Sorento are much faster both in acceleration and top speed. 52 years of progress.

regards
Mech

The 1999 Nissan Maxima is averaging 23.6 MPG based on 13 drivers and 688 fuel ups. Two screwups that you noted are not going to change the numbers notably. The graph at 1999 Nissan Maxima MPG Reports | Fuelly looks normal -> no systematic bias.

As I understand it, the EPA does an independent, third-party estimate of each car's mileage. If there is a major, consistent discrepancy between EPA estimates and actual end-user experience, then the problem lies in the differences between testing and real-world scenarios. While there is probably no conspiracy on the fuelly website, I think it is equally unlikely that there is a conspiracy with the EPA's testing.

More than likely, Hondas respond poorly to the EPAs testing but better in the hands of average drivers, while Hyundais do well in the EPA's testing but poorly in the hands of real drivers.

I'd also be curious to see the demographic breakdown of the people who are reporting. It's very possible that people who bought Hyundais instead of Hondas saved enough money in the initial purchase that they aren't as concerned with getting great mileage/paying less for gas. It's also possible that older people are more likely to be able to afford the "better brand," and as a result you have older (and consequently more subdued) drivers in the Hondas.

But in the end, there are just too many factors to take into account. Let the EPA do their jobs, and if they've gotten it wrong, they should check the reasons why. This isn't the same as GM advertising the Cruze at 45 mpg before the EPA even had a chance to rate it.

...for the curious, here's what GM "...sent to..." EPA for the 2012 Model Year Cruzes and Sonics:

http://www.epa.gov/otaq/datafiles/FO...1_APPIPT1_.PDF

Got 44.7 on a 63 mile highway trip today, about 10 of which was in town.
But, of course, I JUST filled up with 90 octane E-ZERO!

And yes, I took a beaker with me and tested it BEFORE filling the car!

Maybe they're the same Prius drivers who pass me doing 80 mph.

The EPA test is here:

Detailed Test Information

Click the "Highway" tab. You'll notice that the initial acceleration takes 29 seconds to get to 36 mph, and it only actually hits 60 mph twice during the entire test. The average is 48.3 mph.

Since the test is almost exactly the same for every car, I could see a manufacturer programming the computer to sense the pattern of driving and adjust factors appropriately to max out the test.

Or perhaps the Hyundai is more aggressive about upshifting, which increases its score on the gentle acceleration of the EPA test, and is also more aggressive about downshifting to make it more "sporty" for drivers.

A lot of cars are programmed to spoof EPA and similar drive cycles. I've noticed that Chevrolets, in particular, have schizophrenic engine mapping to ensure that at part-throttle operation, they're making much less power than they could, simply so they can meet some emissions or economy target (makes for funny dyno charts, with a huge valley straight down the middle).

I wouldn't put it past Hyundai to use a similar sort of system on their drive-by-wire cars, I've seen Hyundai test-units do good-to-great economy numbers on my typical eco-minded drive, but when you add a bit of zing to the drive, overtaking, accelerating often, the numbers seem to drop badly, so in average use, they're not quite as good as the Hondas I've driven.

And a number of people have noted (there was an issue about this locally) that Hyundai cars are tuned on the edge, making them sensitive to octane. A Shell engineer from overseas also mentioned this to a friend a while back. Octane sensitivity will mean that when you get a bad batch of gas, power and economy suffer. Hondas seem perfectly happy with low octane, as revealed by a magazine article a while back that noted an Accord makes more power with lower octane gas!

And Honda is one of the few manufacturers that seems perfectly content to let their engines do their thing. No weird engine mapping or strange power-sapping fuel-saving strategies. This allows average users to get the acceleration they want with a little tickle of the throttle, whereas said drivers presented with an engine mapped specifically for fuel efficiency will have their foot deeper in on the throttle at all times out of frustration.

In the end, YMMV. In our country, people complain about the fuel economy of Hondas because our driving cycle is vastly different. Less high speed cruising (where Hondas seem to excel) and more bumper-to-bumper 5 mph crawls, where the extra ratios on Hyundai six-speed automatics help quite a bit. (though people still complain about their economy)

Sorry. Nobody is buying the conspiracy theories.

Who are you talking to?

Facts are a hard reality.

83 2011 Elantra owners have filled up their cars 2095 times, have driven 618,714 miles, are averaging 30.7 mpg, thought they'd get something from 29/33/40, and apparently, based on the OP, are unhappy. (Hyundai Elantra MPG Reports | Fuelly)

A hard reality indeed.

30.7 looks like it's between 29 and 40.

Unhappy with their own driving habits and looking to blame somebody else. Quite the 'fact' you got there. I wouldn't hang my hat on it.

Guess they think being in an econo box allows them to flat foot it all the time...

FYI, Pop Mechanics recently ran a fuel economy test using the Elantra (and Ford Focus). You can decide for yourself how valid their test method was (described in the article).

They found that their Elantra was good for 47.6 mpg (US) @ 55 mph and 39.3 mpg (US) @ 70 mph on their highway run. In their city loop, they measured 34.1 mpg (US).

Recall city/hwy EPA ratings for the car are 29 / 40 mpg (US).

http://www.popularmechanics.com/cm/p...04-0212-de.jpg

Source: Mileage Moment of Truth - We Put 40 Mpg Claims to the Test - Popular Mechanics

As the manufacturers extract better mileage out of their designs, it will become much more difficult to beat EPA figures by a significant margin without significantly lowering your average speed.

The wife's Kia Sorento with the GDI 2.4 is averaging about 26 on her local stop and go driving. It's rated at 32 highway. Her previous car, an 09 Nissan Rogue, was rated at 27 highway. She regularly averaged 28 MPG in the Rogue driving basically the same routes over the years and tens of thousands of miles.

The Sorento weighs 3800 pounds, about the same as a Murano, while the Rogue was about 500 pounds lighter.

Best ever mileage for me in her Rogue was 33 MPG. I haven't driven a back roads 55 MPH average trip in the Sorento, but I would bet the mileage would be about the same.

I have seen over 32 on the Interstate and we recently removed the roof rack cross braces. In traffic I have seen 35 MPG, exceptional mileage from a 3800# CUV. Not overall for a trip but for 15 miles.

Bottom line, it was easy for her to beat highway EPA in her local driving in the Rogue. Best I have ever done with the Sorento is about 29 MPG on a local route drive, which is just about the same as I would have done in the Rogue.

I think cold weather (and we have nothing but E10 here) have a more significant effect on the direct injection engine mileage, both the E10 and the cold weather. It will be interesting to see what happens in warmer weather, and the EPA should stop using E0 in any testing since it is getting to the point where that fuel is no longer available in most of the parts of the country anymore.

regards
Mech

The reason they're squeezing such good MPG numbers out of all these new cars is because they're using the VVT to run the atkinson cycle at part load. They're able to switch back and forth between atkinson and otto cycle very quickly so the driver never notices a loss in throttle response and torque. Even the mustang is using this trick.

tjts1 -

That's a cool detail to know. I will look for this detail in the literature.

CarloSW2

It didn't even occur to me until I read it in a Mustang article.
http://www.greencarreports.com/news/...id-tech-tricks

We got a 2012 AT Elantra. Drove it 2300 miles all highway from Louisiana to California. First 1200 miles at the PSL (as high as 80 mph in west TX), averaged just ~36 mpg.

Last 1100 miles I aired the tires up to 51 psi and drove between 60 and 65 mph, and averaged something like 44.7 mpg.

Hyundai/Kia MPG claims busted by EPA
 

Hyundai admits their ratings were inflated by 2-3 MPG after an investigation by the EPA.

The company blamed it on "procedural errors" and will compensate owners.

Hyundai, Kia admit exaggerated mileage claims, will compensate owners

See also: Detroit News - http://www.detroitnews.com/article/2...372/1148/rss25

EPA press release: http://yosemite.epa.gov/opa/admpress...d?OpenDocument

"Procedural errors" sure... I wonder how many sales this 'error' netted them.

I just saw this EPA report in today's LATimes, but I gotta say, the Sonata I rented last summer in PA was remarkable in 6th gear, down around 1700/1800 RPMs at 60mph, IIRC. The Elantra auto trnas also has that gearing. I'll try to talk my wife out of her 2010 Subaru Forester and into one of these in a year or two, when she can get a dealer-certified used one with much of its heaviest depreciation already complete.