Soon after the Environmental Protection Agency revealed that German automaker Volkswagen’s diesel vehicles cheated EPA standards, Volkswagen’s CEO Martin Winterkorn resigned Sept. 23 due to the scandal’s pressure. Replacing him is Matthias Müller, former chief of Volkswagen’s Porsche brand, who now faces the challenge of restoring Volkswagen’s trustworthiness.

Although diesel cars aren’t popular in the United States, Volkswagen sought to counter that by convincing Americans of their eco-friendliness. Ironically proving the opposite point, the cars regularly failed to adhere to the EPA’s regulations. According to The Economist, the cars were at least 40 times over the allowed limit of nitrogen-oxide emissions. The vehicles only initially passed because they were equipped with software that recognized when testing occurred and altered emissions accordingly.

The emergence of the scandal collapsed Volkswagen market stock and may have more consequences. Volkswagen could face billions of dollars in fines, as well as reduced car sales. German officials also expressed fear of an overall reduction in German export value. Müller will be tasked with reversing the damage, though some experts predict Volkswagen may not quickly recover from the damage to its reputation.