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Discussion Starter · #1 · (Edited)
Here's Why Real-World MPG Doesn't Match EPA Ratings - Edmunds.com

edit: It seems this site's link transformation that makes the above point to jdoqocy.com busts the link. You might need to copy and paste the URL below.
Code:
http://www.edmunds.com/fuel-economy/heres-why-real-world-mpg-doesnt-match-epa-ratings.html
Has this happened to you? You go shopping for a new car and great fuel economy is high on the list of things you want. You buy a car that's rated 30 mpg on the highway and 28 mpg overall by the Environmental Protection Agency (EPA). But after a month or so of driving around, you find that the best fuel efficiency you can get is a measly 24 mpg average. You might acknowledge that you drive a little faster than the speed limit, but you're no hot-rodder.

So why doesn't your fuel economy match the EPA rating?...
If one wants more info on the EPA tests, please look at http://www.cruzetalk.com/forum/27-f...uth-about-epa-city-highway-mpg-estimates.html.
 

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Maybe because your **** car isn't broken in yet? Maybe because its 30F outside.? Maybe you haven't quite figured out where the engines most efficient powerband is yet? Maybe you haven't figured out what fuel brand / grade works the best? Or maybe you just drive like a jackass?!! Maybe its all of these! We have how many threads about this?

EDIT: That was a little harsh, but seriously how many articles will they come up with criticizing the EPA and car manufacturers without holding the driver accountable?
 

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Discussion Starter · #3 · (Edited)
Yep, the driver plays a large role. I see so many bad habits for FE, like the below...

Even at >$4/gallon for regular here, gas must still be too cheap (and/or the drivers too ignorant) when I still see a whole bunch of cars including a few monstrosity class (full-sized) SUVs getting into VERY LONG drive-thru lines at fast food joints. I guess getting 0 mpg for a few to many minutes at a time is something they don't consider.

I saw the above today and not a single one was a hybrid, so no ICE auto-stop for them.
 

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Yep, the driver plays a large role. I see so many bad habits for FE, like the below...

Even at >$4/gallon for regular here, gas must still be too cheap (and/or the drivers too ignorant) when I still see a whole bunch of cars including a few monstrosity class (full-sized) SUVs getting into VERY LONG drive-thru lines at fast food joints. I guess getting 0 mpg for a few to many minutes at at time is something they don't consider.

I saw the above today and not a single one was a hybrid, so no ICE auto-stop for them.
These are the same people that are 50 pounds overweight and can't understand why they can't lose a few pounds.
Also, makes me crazy seeing some people cruising the parking lot for a half an hour looking for a space 20 feet from the door of the store instead of just parking the car and walking. I never use the drive-thru. Just park the car and walk inside! How hard is that? Disabled folk are exempt from this rant.
 

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I, for one, tend to get better than EPA advertised MPG numbers (real, not DIC calculated) driving faster than the posted limit. My last car didn't, however, and neither does my family's other car, a Honda Pilot.

YMMV, so to speak.
 

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I, for one, tend to get better than EPA advertised MPG numbers (real, not DIC calculated) driving faster than the posted limit. My last car didn't, however, and neither does my family's other car, a Honda Pilot.

YMMV, so to speak.
Likewise. 37 MPG on two occasions over 400 miles in the Cruze going 65-70 mph, and the test is done at 55-60 mph. -_-
 

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I don't believe the EPA accurately reflects what peoples' gas mileage is going to be and I'm running based on the initial post. I believe this applies both to people getting over and under the rated fuel economy. I also don't believe they correctly account for all variables and modifications to a car from the factory that can affect fuel economy.

I repeat the example of the Cruze Eco Auto. Acccording to the EPA, this car gets the same city mileage as the 1LT/2LT/LTZ and only one mile per gallon better on the highway. The following modifications are included:

Underbody skid panels
Grill shutter
Lip spoiler
Forged alloy wheels that are 21lbs lighter (over all 4) than the 16" alloys
Low rolling resistance tires
A ~100lbs weight reduction over the 1LT and ~150lbs reduction over the LTZ.
10mm lowered springs

All of those considered, providing a notable weight reduction and what I've read to be a 10% drag reduction account for absolutely no difference in city mileage and only 1mpg difference in highway mileage?

Meanwhile, you'll be hard pressed to find a person who drives a Cruze Eco MT like a sane person who doesn't achieve over the EPA rated fuel economy on both city, highway, and average.

I get the feeling that there are things the EPA isn't accounting for in their fuel economy estimations.
 

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I repeat the example of the Cruze Eco Auto. Acccording to the EPA, this car gets the same city mileage as the 1LT/2LT/LTZ and only one mile per gallon better on the highway. The following modifications are included:

Underbody skid panels
Grill shutter
Lip spoiler
Forged alloy wheels that are 21lbs lighter (over all 4) than the 16" alloys
Low rolling resistance tires
A ~100lbs weight reduction over the 1LT and ~150lbs reduction over the LTZ.
10mm lowered springs

All of those considered, providing a notable weight reduction and what I've read to be a 10% drag reduction account for absolutely no difference in city mileage and only 1mpg difference in highway mileage?

Meanwhile, you'll be hard pressed to find a person who drives a Cruze Eco MT like a sane person who doesn't achieve over the EPA rated fuel economy on both city, highway, and average.

I get the feeling that there are things the EPA isn't accounting for in their fuel economy estimations.
I disagree. You are overestimating the impact of 100 lbs of weight. That is the difference between ~1/3 vs. a full tank. Weight does make a difference, but its not nearly as sensitive as many people believe. You have to tack on a few hundreds lbs for the fuel economy to start dropping off in city conditions. These engines have plenty of torque for an extra ~100 lbs. Sure, its an incremental increase, but the EPA testing cycle isn't too inaccurate in these variables on the city cycle. It is a decent baseline. The EPA screws up mainly on the highway cycle where aero improvements and speed play a bigger factor.

Then you get to the aerodynamic differences. They are only significant at higher speeds. At 55 mph where the cycle is, they will only make a 1 MPG difference. The dyno that this is performed in does factor these things in. 55 mph is not a lot of aero drag, which is why the difference isn't high. But we know drag increases to the third as speed increases, which is why wind resistance is a bitch OVER 60 mph.

Go look on fuelly, you don't see to many Auto Ecos to begin with, and chances are unless they are all highway driving, their fuel mileage won't be too different from other 1.4L models. Hate on the EPA all you want, but they aren't just pulling numbers out of a hat. There is a consistent scientific methodology for their results, even if it is based on more ideal scenarios.
 

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See the test I posted earlier. Drag does in fact make a huge difference at 55mph over even 45. The test was done by someone with the cruze eco mt over on cleanmpg.

I think 100lbs makes a notable difference. Go buy a few bags of rocks and see what the difference is in your car. The difference will be noticeable.

Sent from my Bulletproof_Doubleshot using AutoGuide.Com Free App
 

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100 lbs in the trunk of the Cruze is definitely noticable. When I do a sand run for my walkway (gotta love expansive soils) I put several 40 lb bags in the trunk. Even two or three bags makes a huge difference in acceleration.
 

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Discussion Starter · #12 ·
I don't see how you can criticize the manufacturer, the EPA rates the cars, the EPA rating sells the cars, they build them to perform well on the EPA test.
No, the EPA does NOT rate MOST cars. The EPA sets the procedure but only tests about 15% of new models.

From The Truth About EPA City / Highway MPG Estimates - Feature - Car and Driver (discussion thread at http://www.cruzetalk.com/forum/27-f...uth-about-epa-city-highway-mpg-estimates.html ):
While the public mistakenly presumes that this federal agency 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.
 

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Does the EPA test at full operating engine temperatures or do they just turn the car on and go? I'd be curious to find that out.
 

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I believe the EPA test assumes full operating temperature.
 

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good thing for the internet where you can find out what people are really getting.

i am only on my 3rd tank and my car is far exceeding the rated city mileage.
 

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Discussion Starter · #16 ·
Does the EPA test at full operating engine temperatures or do they just turn the car on and go? I'd be curious to find that out.
I believe the EPA test assumes full operating temperature.
It depends on which test. See Detailed Test Information under Detailed Comparison.

If you're asking such questions, I suggest you read the 3 links I mention at http://www.cruzetalk.com/forum/27-f...uth-about-epa-city-highway-mpg-estimates.html.
 
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