Hyundai Motor America and Kia Motors America will lower the fuel economy ratings for more than one million vehicles sold in the US and Canada, after an EPA investigation found the automakers overstated mileage claims in 13 models.
The auto companies, which are both owned by Hyundai Motor Group, said they will lower fuel economy ratings for about 900,000, or 35 percent, of the group's 2011-2013 model year vehicles sold in the US through October 31, 2012. Another 172,000 vehicles sold in Canada also had overstated mileage claims, Hyundai and Kia said.
The companies will relabel vehicles currently in showrooms in US and Canada. Hyundai has agreed to compensate owners for additional fuel costs as well.
Mileage on most vehicle labels will be reduced by one to two miles per gallon, the EPA said. The largest adjustment will be for the Kia Soul, which had overstated its fuel economy by 6 mpg on the highway and 3 mpg in the city.
Overstated mileage was found on numerous Hyundai 2012-13 models, including Accent, Azera, Elantra, Genesis, Sonata, Tucson and Veloster, the EPA said. Hyundai's 2013 Santa Fe (pictured) also had inflated mileage estimates. Kia 2012-13 models in the Optima, Rio, Sorento, Soul and Sportage car lines also had incorrect fuel economy claims, the EPA said.
Hyundai and Kia blamed procedural errors during a process called "coastdown" testing, at the automakers' joint testing operations in Korea, for the incorrect fuel economy ratings. Coastdown testing simulates aerodynamic drag, tire rolling resistance and drivetrain frictional losses and provides technical data used to program the test dynamometers that generate EPA fuel economy ratings.
Customers will receive a personalized debit card that will reimburse them for their difference in the EPA combined fuel economy rating, based on the fuel price in their area and their own actual miles driven. Hyundai will add an extra 15 percent to the reimbursement amount in acknowledgement of its error. Current owners will be able to refresh their debit cards for as long they own the vehicle. The same formula will be used to reimburse prior owners of affected vehicles.