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(credit: valérie kuki)
This week brought confusion for General Motors and its German subsidiary Opel.
US-based General Motors told the Environmental Protection Agency (EPA) that it had misstated the fuel economy on some 130,000 Chevy Traverses, GMC Acadias, and Buick Enclaves from 2016, overestimating the cars' mileage by 1-2 miles per gallon. GM has said it will compensate customers for the miles per gallon they thought they were getting, possibly with gift cards. The automaker also halted the sales of another 60,000 affected vehicles.
GM said that the misstated mileage came from incorrect calculations made by the company when it was updating numbers for their 2016 models. The company said that new “emissions-related” hardware had changed the cars' miles per gallon, and GM failed to take that change into account. GM noted that its engineers discovered the error as they were working on the 2017 models.