By Jeff Plungis, Bloomberg News
WASHINGTON (Sept. 29, 2015) — Volkswagen A.G.'s ability to cheat on emissions screening for seven years is putting pressure on U.S. regulators to change the assessments by adding more road tests to complement laboratory analysis.
The U.S. Environmental Protection Agency (EPA) vowed last week to do more spot-checks on data generated from indoor labs. Yet the agency remains wary of broader use of road tests, saying they are costly and the lab tests are still needed for scientific and legal accuracy.
Environmental groups called the EPA's approach flawed.
“What we're doing now isn't keeping polluting vehicles off the road,” said Dan Becker, director of the Washington-based Safe Climate Campaign. “The VW scandal proves auto makers cheat, and that means the rules have to change.”
There is precedent for on-the-road spot tests: The EPA began conducting them on trucks decades ago after a similar scandal. For now though, the agency is sticking with the carefully proscribed tests it conducts on treadmill-like dynamometers — the ones VW engineers programmed their cars to evade.
For decades, regulators have relied on auto makers' tailpipe tests to keep the air clean. Auto makers test new models in the lab according to procedures designed by the EPA. Regulators look at the results and ask questions if they look suspicious. The agency does spot checks on about 15 percent of the fleet.
Non-profit group
But that failed to detect Volkswagen's cheating, which was ultimately discovered by a non-profit group that mounted monitors to cars and drove them up and down California.
The German car maker has admitted fitting as many as 11 million diesel cars with software that detected when a test was being run and altered the engine performance so it would pass. The company has suspended sales of those vehicles and CEO Martin Winterkorn resigned from the post as investigators from Washington to Berlin have promised to punish those responsible.
“This is a warning that the regulators can never afford to let down their guard,” said John DeCicco, a researcher who worked on overhauling EPA test procedures in the 1990s. “They can't just accept lab results.”
The EPA was under fire two decades ago after real-world tests showed gasoline-powered cars were emitting far more pollution than lab tests suggested they should, Mr. DeCicco said.
The agency hired technicians with remote sensing systems to go to places like tunnels, where emissions are concentrated, or freeway entrances, where cars are accelerating. They compared readings with what models suggested pollution levels should be according to auto makers' lab results.
There were huge discrepancies, Mr. DeCicco said. Auto makers were designing their systems according to a federal test cycle developed in the 1970s. The test was run too slow and with air-conditioning off, which skewed the results.
Truck tests
In response, the EPA overhauled its lab tests to more closely mimic the way drivers actually drive. They added more acceleration, higher top speeds, aggressive starting and stopping and turned air-conditioning systems on.
The EPA has equipped big-rig trucks with emissions-measuring devices since a 1998 consent decree signed by truck makers. Since the 2007 model year, the agency has been compiling real-world pollution data, according to Public Employees for Environmental Responsibility (PEER), a watchdog group of government workers and retirees based in Washington.
The EPA hasn't posted that data publicly or released it in a way that independent researchers can see what's going on.
The VW scandal “suggests EPA's handle on the actual amount of auto emissions may be substantially off,” said Jeff Ruch, the group's executive director. “This scandal shows that dynamometer technology is a dinosaur yet EPA keeps pouring money into it.”
The EPA has released the vast majority of the testing data to Mr. Ruch's group in response to a Freedom of Information Act request, agency spokeswoman Julia Valentine said in an email. The only data withheld was confidential business information, she said.