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Hyundai Elantra Real World MPG 2012

745 messages,  Last post on May 18, 2013 at 10:29 AM

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What is this discussion about? Hyundai Elantra, Fuel Efficiency (MPG), Hatchback, Sedan

Messages Page 54 of 75

#531 of 745 Re: Use today's EPA method & data for our Elantras [m6user] by backy

Jun 18, 2012 (8:42 am)

Replying to: m6user (Jun 18, 2012 7:16 am)
Most people realize if they drive in extreme conditions.
 
I am beginning to doubt that, based on the posts I've seen in the "fuel economy" discussions. Perhaps many people don't realize how extreme (compared to the EPA test regimen) their driving conditions are because: 1) they are "normal" for them, and 2) they don't know the details of how the EPA does its tests.
 
So they drive a car that, let's say for discussion sake, has an EPA rating (based on 2008 figures) of 21/29 with 24 mpg average. They have been able to achieve the 24 mpg number in their everyday driving. (And note this is a fully broken in car.) So they buy a new Elantra and expect they will achieve at LEAST 33 mpg, the EPA average FE number, in their everyday driving. And let's say they were able to achieve at least 29 mpg on the highway with the old car. So they expect to achieve at least 40 mpg with the new Elantra. Unreasonable assumptions? No. But maybe not good assumptions.
 
Why not? First, it's a lot easier for a car to achieve 24 mpg average or 29 mpg highway than for a car to achieve 33 mpg average and 40 mpg highway. For the two cars I am talking about here--a 2004 Elantra and a 2013 Elantra--the 2013 Elantra has 10 more hp and the weights are within a few pounds of each other. The 2013 has a 6AT vs. 4AT and is more aerodynamic, so it should be able to achieve better FE than the 2004. But at low speeds, as in city driving, those advantages are minimal at best. They really kick in on the highway, where the engine can rev lower due to the two additional cogs and the aerodynamics help--up to a point! Start driving over about 65 mph, and wind resistance will cut that FE quite a bit (which I saw first-hand on a long trip this weekend in a 2007 Sonata--FE went down considerably over 65 mph).
 
The other thing is, the old car and the new Elantra are different cars (duh). Thus what worked fine for getting at least the EPA rating on the old car may not lead to optimal FE in the new Elantra. It has different hp, differnt hp to torque ratio, it's geared differently, etc.
 
Please note that I am not saying that people who complain about the FE on their Elantras are stupid or crazy or whatever. But there are factors that can explain, other than "it's a conspiracy by Hyundai" or some-such, why some people can't hit the EPA numbers on their new Elantras when they were able to do it on their old cars. And there's also the possibility of sample defects (e.g. 4,000 complaints--a lot of complaints!--out of the 400,000 or so 2011+ Elantras sold to date is 1%--well within the range that can be explained by sample defects).

#532 of 745 Re: Use today's EPA method & data for our Elantras [backy] by m6user

Jun 18, 2012 (8:58 am)

Replying to: backy (Jun 18, 2012 8:42 am)
At least you're recognising that there is a possiblility of a 1% defect rate unlike many so called experts in here.
 
I agree wholeheartedly that most people don't know exactly what their true ratio city/hwy is. But I maintain that most have a pretty good idea. But I'm confused on your example. Why is it easier for the 2004 Elantra to achieve 24 city on the EPA test than it is for the 2013 Elantra to achieve 29? We're not talking wind resistance and the added hp and tranny ratios should still be an advantage even at lower speeds. Since it's a pretty standard test, shouldn't the 2013 Elantra be able to achieve it's rated city mpg just as easy? If not, should it really be rated at 29 city. I'm not so hung up on the EPA numbers per se, but I do use them for comparison as every car goes throught the same exact testing.
 
Maybe I'm missing something which has been known to happen from time to time.

#533 of 745 Re: Use today's EPA method & data for our Elantras [m6user] by backy

Jun 18, 2012 (10:27 am)

Replying to: m6user (Jun 18, 2012 8:58 am)
Why is it easier for the 2004 Elantra to achieve 24 city on the EPA test than it is for the 2013 Elantra to achieve 29?
 
I have no idea. That's not what I said in my post, and the EPA city rating of the 2004 Elantra is 21, not 24.
 
What I said was, it's harder for a car to achieve 33 mpg overall than 24 mpg overall. That's a 38% increase in fuel economy--for two cars that are about the same weight, the one with 33 mpg average is more powerful, and as I mentioned, the factors that work towards the high mpg don't come into play much in the lower-speed driving. Also, 40 mpg highway is harder to achieve than 29 mpg for two cars about the same size and weight and power (again, the higher mpg car is actually more powerful). Plus I see many folks comparing a well-broken-in car to a brand-new car, or one with only a few thousand miles on it. My experience with two Elantras purchased new is that FE improved over the first few thousand miles and got better up past 15k miles. And now at 70k miles my 2004 is still doing much better on FE than when new (always had recommended maintenance of course).
 
The 2013 Elantra should be able to meet its EPA city rating in city driving... of the kind similar to how the EPA runs its city cycle tests. I find when I drive a car--any car--in real-world all-city driving, I have a real hard time meeting the EPA rating. As I said, I don't think a lot of people have any idea how much their "city" driving differs from what the EPA considers "city" driving.

#534 of 745 Re: Use today's EPA method & data for our Elantras [m6user] by gman4911

Jun 18, 2012 (11:08 am)

Replying to: m6user (Jun 18, 2012 8:58 am)
People who are frustrated with not getting the EPA numbers don't understand how the tests are done. It's easy enough to prove to yourself whether or not it's possible for a 2011+ Elantra to meet the EPA numbers and whether or not you have a defective car - drive it the way the EPA did.
 
In the city, it means an 11 mile route with no stop lights, stop signs are ok, little to no traffic i.e. no rush hour traffic, gentle acceleration, total idle times of not more than 5.6 minutes, avg speed 21 MPH, top speed 56 MPH, as level terrain as possible, nice weather, no A/C.
 
On the highway, it means a 10 mile route with little to no traffic, your avg speed is 48 MPH, your top speed is 60 MPH, as level terrain as possible, nice weather, no A/C.
 
That's all the EPA tests do except in a lab with the car on a dynomometer and with 100% gas, not 10% ethanol. They don't drive the car for one tank of gas and calculate the MPGs. The posted EPA numbers are the MPGs attained from driving those two scenarios. If you can't get the EPA numbers under the driving scenarios above, then it's possible you have a defective car.
 
Once you've determined it's possible for the car to achieve the numbers, then any differences over the entire tank of gas is due to differences in driving styles, traffic conditions, terrain differences, weather conditions, etc.
 
When Popular Mechanics test drove the Elantra and Ford Focus, they did everything they could to mimic the EPA test but in the real world, and exceed the EPA numbers.

#535 of 745 Re: Use today's EPA method & data for our Elantras [gman4911] by m6user

Jun 18, 2012 (3:33 pm)

Replying to: gman4911 (Jun 18, 2012 11:08 am)
I guess the EPA needs to revise the testing methodology again. Prior to 2008 people were complaining so the EPA revised their tests and made it more realistic. Now, it seems with these high MPG cars, the EPA tests are unrealistic again. Are we going to go through this cycle every few years each time cars make any kind of jump in MPG?
 
I guess I have to agree with Backy that achieving the EPA numbers in these newer cars is harder and harder. Time for another revision...but just for cars made after 2011 or 2012 I guess or only cars that are supposed to be able to achieve a combined MPG of, say, 33 or better.
 
Or maybe a better way of posting the EPA numbers would be to forget the city/hwy/combined and just post the ranges for city and hwy like the fine print does now. Now that would a lot more realistic but I don't know if the car manufacturer lobbies would want that.

#536 of 745 Re: Use today's EPA method & data for our Elantras [m6user] by backy

Jun 18, 2012 (4:27 pm)

Replying to: m6user (Jun 18, 2012 3:33 pm)
I think the main problem is with the "city" EPA estimates. From what I've seen in many sources, including auto mags, CR tests, and owner posts, it's easier to hit the highway estimates in the real world if one doesn't go over 70 mph or so. CR usually meets or exceeds the EPA numbers for highway driving, for example. But "city" in the real world, for many people, seems to be a lot more severe than "city" in the EPA tests. So I'd focus there if the EPA is to change the test regimen.

#537 of 745 Re: Use today's EPA method & data for our Elantras [gman4911] by dodgeman07

Jun 18, 2012 (9:07 pm)

Replying to: gman4911 (Jun 18, 2012 11:08 am)
There's so much mis-information in this post, I'll just link the EPA test criteria here. It includes 18% idling time for the city, 80mph driving factored into highway, and tests with A/C on.
 
EPA Test Information

#538 of 745 Re: Use today's EPA method & data for our Elantras [gman4911] by m6user

Jun 18, 2012 (9:17 pm)

Replying to: gman4911 (Jun 18, 2012 11:08 am)
On the highway, it means a 10 mile route with little to no traffic, your avg speed is 48 MPH, your top speed is 60 MPH, as level terrain as possible, nice weather, no A/C.
 
Where did you get this information?

#539 of 745 Re: Use today's EPA method & data for our Elantras [dodgeman07] by gman4911

Jun 18, 2012 (9:44 pm)

Replying to: dodgeman07 (Jun 18, 2012 9:07 pm)
What part is mis-information? Everything I listed came from that site. I just did not point out EVERY test.

#540 of 745 Re: Use today's EPA method & data for our Elantras [m6user] by gman4911

Jun 18, 2012 (10:04 pm)

Replying to: m6user (Jun 18, 2012 9:17 pm)
Source
 

Messages Page 54 of 75

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