Press statement

New revelations of Clean Air Act violations by Volkswagen

The International Council on Clean Transportation once again commends the U.S. Environmental Protection Agency and the California Air Resources Board for their rigorous, effective work to enforce the laws governing air pollution from vehicles. The agencies, in collaboration with Environment Canada, yesterday announced that they had discovered additional defeat devices employed on certain VW, Audi, and Porsche light-duty diesel vehicles equipped with 3.0 liter engines. The software included two different operating modes that allowed those vehicles to pass certification tests but then to emit up to nine times the amount of nitrogen oxides (NOx) permitted under U.S. regulations when operating in “normal” mode.

“First and foremost, full marks to the agencies,” said ICCT Executive Director Drew Kodjak. “It’s been little more than a month since they announced new real-world testing, a remarkably rapid implementation—and coming on the heels of the difficult achievement of detecting defeat devices on VW vehicles in the first place.”

Mr. Kodjak noted that a much higher level of detail was provided in the EPA Notice of Violation (NOV) concerning the tactics used to defeat the certification test, which could prove useful to other governments. For example, the NOV disclosed that the defeat device changes engine calibrations, which yields higher levels of NOx from the engine, in addition to affecting NOx aftertreament. “The big-picture lesson here is that regulatory agencies around the world need the authority and technical capacity to do compliance testing and take enforcement actions comparable to those that are allowing EPA and CARB to bring these problems to light and force a remedy.”

Today’s EPA/CARB action highlights again the importance of tackling real-world emissions around the world. Last week, the European Commission’s Technical Committee on Motor Vehicles reached an agreement on details concerning Europe’s Real-Driving Emissions regulation. The agreement proposes significantly less stringent limits on NOx emissions during on-road tests than had been anticipated, and would also delay implementation.

Anup Bandivadekar, ICCT’s passenger vehicle program director, said that “the defeat devices found by EPA and CARB and excess on-road emissions that can be traced back to shortcomings in a type-approval and in-use testing protocol are two faces of the same regulatory problem. Manufacturers must be forced to meet air-quality and vehicle efficiency standards in the real world, and regulators need the tools and authority that will enable them to do that.”

For further information

U.S. EPA Notice of Violation, Nov. 2, 2015

CARB letter to Volkswagen Group of America and others, Nov. 2, 2015

U.S. EPA Notice of Violation, Sept. 18, 2015

CARB letter to Volkswagen Group of America, Sept. 18, 2015


Drew Kodjak, executive director (Washington DC),
John German, US program co-lead (Ann Arbor),
Anup Bandivadekar, passenger vehicles program lead (San Francisco),
Peter Mock, managing director, ICCT-Europe (Berlin),

Vehicle testing