(Reuters) -- Daniel Carder, an unassuming 45-year-old U.S. engineer with gray hair and blue jeans, appears an unlikely type to take down one of the world's most powerful companies.
But he and his small research team at West Virginia University may have done exactly that, with a $50,000 study which produced early evidence that Volkswagen was cheating on U.S. vehicle emissions tests, setting off a scandal that threatens the German automaker's reputation and finances.
The scandal led VW CEO Martin Winterkorn to resign -- and more executives are expected to depart as others responsible for the cheating are identified.
"The testing we did kind of opened the can of worms," Carder says of his five-member engineering team and the research project that found much higher on-road diesel emission levels for VW vehicles than what U.S. regulators were seeing in tests.
Carder said he's surprised to see such a hullabaloo now, because his team's findings were made public nearly a year and a half ago.
"We actually presented this data in a public forum and were actually questioned by Volkswagen," said Carder.
The results of that study, which was paid for by the nonprofit International Council on Clean Transportation in late 2012 and completed in May 2013, were later corroborated by the U.S. Environmental Protection Agency and California Air Resources Board.
Carder's team -- a research professor, two graduate students, a faculty member and himself -- performed road tests around Los Angeles and up the West Coast to Seattle that generated results so pronounced that they initially suspected a problem with their own research.
"The first thing you do is beat yourself up and say, 'Did we not do something right?' You always blame yourself," he told Reuters in an interview. "(We) saw huge discrepancies. There was one vehicle with 15 to 35 times the emissions levels and another vehicle with 10 to 20 times the emissions levels."
Despite the discrepancies, a fix shouldn't involve major changes.
"It could be something very small," said Carder, who's the interim director of West Virginia University's Center for Alternative Fuels, Engines and Emissions in Morgantown, about 75 miles south of Pittsburgh in the Appalachian foothills.
"It can simply be a change in the fuel injection strategy. What might be realized is a penalty in fuel economy in order to get these systems more active, to lower the emissions levels."
Discrepancies in Europe
The ICCT's research contract to Carder's team was sparked by separate findings by the European Commission's Joint Research Centre, which showed a discrepancy between test results and real world performance in European diesel engines.
The diesel vehicles chosen for the West Virginia study were the VW Passat, the VW Jetta and the BMW X5. Unlike the VW vehicles, Carder said the BMW vehicle "performed very nicely -- at, or below, the certification emission levels."
WVU is not new to ground-breaking emissions research, having helped create the first technology to measure vehicle emissions on the road more than 15 years ago.
Carder belonged to a 15-member WVU team that pioneered portable emissions testing as part of a 1998 settlement between the U.S. Justice Department and several heavy duty diesel engine makers including Caterpillar Inc. and Cummins Engine Co.
The manufacturers agreed to pay $83.4 million in civil penalties after federal officials found evidence that they were selling heavy duty diesel engines equipped with “defeat devices” that allowed the engines to meet EPA emission standards during testing but disabled the emission control system during normal highway driving.
Been there, done that
When the news about VW broke last Friday, Carder heard from some of the heavy diesel engine manufacturers that were part of the consent decree.
"They saw what had happened and called to say: 'Good job, you guys,'" Carder said. "Some folks said: 'How did they not learn from our mistakes 15 years ago?'"
Regarding his role in unearthing the current scandal, Carder said there was no particular sense of excitement when his team confirmed that the higher VW emission results were real and not a consequence of faulty measurements.
"There's no incentive for us to pass or fail," he said. "Obviously, we don't want to see something spewing emissions and polluting the environment. But we really have no horse in the race, as they say."