The fix will be a software patch for 90,000 units of the 2012-2014 Volkswagen Passat TDI sold in the U.S. These cars are equipped with so-called Generation 2 emissions control technology as part of their EA189 four-cylinder turbodiesel engines. These engines employ exhaust fluid to incite a chemical reaction that removes harmful nitrogen oxide emissions.
The EPA will need to evaluate and approve the fix before it goes into effect. Earlier estimates projected the software fix would happen in mid-2016.
“We have a long list of questions for VW about this,” EPA acting assistant administrator for air quality Janet McCabe told reporters at the agency’s Ann Arbor, Michigan emissions facility earlier this week. “We’re getting some answers from them, but we do not have all the answers yet.”