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Hyundai Motors re-evaluates its mpg ratings

“Hyundai and Kia Initiate Voluntary Program to Adjust Fuel Economy Ratings on Select Vehicles
Automakers’ Average Fleet Fuel Economy Rating Reduced 3 Percent; Affected Vehicle Owners to be Compensated”

“ORANGE COUNTY, Nov. 2 – Hyundai Motor America and Kia Motors America today announced that, following discussions with the U.S. Environmental Protection Agency (EPA), they are voluntarily adjusting the fuel economy ratings for approximately 900,000, or 35 percent of, 2011-13 model year vehicles sold through October 31, 2012…”

Apparently the manufacturers supply the EPA with certain technical specs which the EPA uses to calibrate their dynamometers. Hyundai and Kia agree to a 3% error, reducing their fleet average from 27 to 26 mpg.

They are offering owners reimbursement for the differences in fuel usage for as long as they own their vehicle. It won’t be very much, but it’s nice to see a manufacturer take responsibility for its actions. See the full article here:

https://hyundaimpginfo.com/news/details/hyundai-and-kia-initiate-voluntary-program-to-adjust-fuel-economy-ratings/

I think most automobile manufacturers overstate their mileage ratings. It’s an estimate anyway which allows for the real up or down “true” mpg. Some aggressive drivers never reach the best estimate regardless of the number.

Manufacturers don’t guess, or estimate, their mileage numbers. The tests are very tightly defined by the government and must be followed to the letter. There are ways to enhance the numbers a bit since the tests are so tightly controlled but discretion is not an option. The biggest variable is always the driver.

Now, that said, there have been some creative solutions to the power vs mileage/emissions problem. One manufacturer of performance cars calibrated their engine to meet the emissions when only the drive wheels were turning, such as on a dyno, but the car used the go-fast calibration when all 4 wheels were turning, such as in actually driving…

Mustangman…the manufacturers do test their vehicles for the best fuel ratings but at the end of the day it’s just an “estimate.” The window sticker on all new vehicles say “EPA Fuel Economy Estimates.” I’ve never seen a new vehicle window sticker that didn’t say it for many years.

@missileman. the US EPA tests every vehicle subject to CAFE mileage ratings. These tests are called estimates because the vehicles are tested on a dynamometer and city or highway conditions are simulated. The good news is that road and weather conditions never change, so the test is identical for all vehicles tested. The bad news is that the test can apparently be spoofed by clever manufacturers who provide optimistic data, which is apparently used in the test. The auto manufacturer can’t change the EPA ratings directly.