Ford Motor Co. admitted overstating the fuel-economy ratings on six 2013 and 2014 models, and agreed to pay owners as much as $1,050 to compensate for underestimating their fuel costs.

It was the second time within a year that the Dearborn, Mich., auto maker has admitted to overstating the mileage ratings on its vehicles. The company said each time overstatements resulted from errors conducting government-prescribed tests.