Volkswagen's Diesel Cars Were Only Clean When Someone Was Watching
For nine years, 11 million cars ran a second, secret program whenever a lab was watching. The rest of the time, they just breathed normally.
From 2006 to 2015, Volkswagen sold diesel cars in the U.S. and Europe advertised as clean, efficient, and quietly excellent — "clean diesel," the ads called it, a phrase doing an enormous amount of work. Under the hood was software that could tell the difference between a lab and a road.
When the car detected the steering position, speed pattern, and duration typical of an emissions test, it switched on full pollution controls. The instant it detected normal driving conditions, it dialed them back down, and the car emitted nitrogen oxides at up to 40 times the legal limit. Regulators only caught on because researchers at West Virginia University got curious why American clean-diesel cars drove so much dirtier than their paperwork claimed.
On September 18, 2015, the EPA issued a formal Notice of Violation. Four days later Volkswagen admitted it: roughly 11 million diesel vehicles worldwide carried the software. CEO Martin Winterkorn resigned within the week, insisting to the end that he personally hadn't known — a defense that requires believing a decade-long global engineering deception ran itself.
The cleanup bill came to $14.7 billion in the U.S. alone: buybacks, compensation, and penalties for roughly 500,000 American drivers who'd paid a premium specifically for the clean part. Which, it turned out, was a feature that only activated when it knew it was being graded — the automotive equivalent of behaving perfectly during the parent-teacher conference and then reverting immediately after.
Filed from public reporting:
