U.S. EPA announces plans to expand road emissions tests for diesel vehicles

Concerned that cheating on vehicle emissions tests could be prevalent across the automobile industry, regulators in the United States and Canada said they will expand their on-the-road emissions tests to cover all makes and models of diesel cars.

The tests, which come in the wake of Volkswagen’s admission that it installed a software on more than 11 million diesel cars to pass U.S. emissions standards, are being conducted randomly and in real-world conditions, rather than in laboratory settings.

“We are very anxious to find out if there are any other programs out there,” said Christopher Grundler, director of the office of transportation and air quality at the U.S. Environmental Protection Agency (EPA).

The first tests on Volkswagen (VW) cars, which were recently completed, found the defeat device on about 10,000 VW, Audi and Porsche brands, which were not previously disclosed by Volkswagen. Volkswagen disputes the EPA’s claim, saying the software was not intended to thwart emissions testing.

Since then, no other automobile company has been found to have installed the defeat device which turns on during dynamometer testing, although it will take several weeks for all makes and models to be tested.

Grundler declined to describe the tests, except to say they will focus on 2015 and 2016 model-year diesel cars. They will also be performed on all new cars that manufacturers seek to certify, he said.

The move by the U.S. EPA is a significant expansion of its testing program, which previously did road testing for pollutants mainly on large trucks. It also conducts spot checks of older cars to ensure that their pollution-control mechanisms are still working. Tests are also being performed in cooperation with Canadian and Californian regulators.

The VW scandal has highlighted deficiencies in existing tests, which are performed in highly controlled environments, in North America and in Europe. Road testing could be more unpredictable and precision data may be more difficult to obtain under such conditions. However, the aim of these road tests is to validate lab findings.