Car manufacturers Hyundai and Kia have made a significant blunder regarding the expected mileage of several vehicle models, which will cost them millions of dollars to compensate for.

Both Hyundai and Kia are owned by the same company, and while they share factory space, each boasts different makes and models of vehicle. The mistake was discovered by the EPA during a study which compared the agency’s test results and the research data turned in by the company, and will require an update of mileage stickers on the affected models as well as various payouts to the consumers who have already been affected by the misinformation.

Spokespeople for Hyundai say the numbers–which show a 1-6 mile per gallon discrepancy–were a complete mistake on their part and were not intended to pull the wool over the eyes of their customers.

“We’re just extremely sorry about these errors,” said John Krafcik, Hyundai’s CEO. “We’re driven to make this right.”

The Kia Soul will take the hardest hit, dropping six miles per gallon for its highway fuel economy estimate to 29.

The company will issue debit cards to those drivers affected to make up for the difference, and says the owners can take advantage of the offer for as long as they own the car. Assuming all 900,000 of those affected accept the debit card deal, Hyundai/Kia is looking at shelling out around $79 million per year.

Image: Kia