Regulators were skeptical about Volkswagen for months

September 24, 2015, 4:38 PM UTC
Volkswagen Group Delivers Over 9 Million Vehicles In 2012
BERLIN, GERMANY - JANUARY 14: Visitors look at VW cars at a Volkswagen Group showroom on January 14, 2013 in Berlin, Germany. Volkswagen Group, which includes the VW, Audi, Porsche, Skoda, SEAT, Bentley and Bugatti brands, delivered a record 9.07 million cars to customers in 2012. Rising sales in the Americas and Asia helped to offset a drop in sales in western Europe. (Photo by Sean Gallup/Getty Images)
Photograph by Sean Gallup — Getty Images

Though Volkswagen only admitted to wide-scale emissions cheating after the U.S. Environmental Protection Agency publicly criticized it last week, a Reuters exclusive report indicates regulators were growing increasingly skeptical of the company for months.

Volkswagen issued a recall for its diesel Audis and VWs in California in April. That recall advised customers to return their cars to dealerships to receive a software update that would ensure emissions were “optimized and operating efficiently,” Reuters reports.

The recall came as Volkswagen was defending itself against the California Air Resources Board, which believed VW’s cars were producing more emissions than the company advertised. According to Reuters, the car company told the CARB that the emissions problem was a ” technical – and easily solved — glitch.” While the recall apparently reduced emissions somewhat, “NOx [nitrogen oxide] emissions were still significantly higher than expected,” the Washington Post reports.

Now that VW has admitted to deceiving regulators, it has recalled the nearly half million vehicles affected in the United States. A total of 11 million vehicles worldwide carry the emissions-cheating software.