Updated 11.02am

THE VOLKSWAGEN EMISSIONS-CHEATING scandal has widened as US regulators said the German automaker also included illegal “defeat devices” on its larger 3.0 litre diesel engines over the past three years.

Volkswagen had already admitted including the software, which cheats pollution tests, in smaller 2.0 litre diesels equipped in some 11 million 2009-2015 model year cars worldwide.

But the Environmental Protection Agency said it had discovered in its investigation that various six-cylinder 3.0 litre diesel VW Touareg, Porsche Cayenne and Audis from the 2014-2016 model years and distributed in the United States had also been rigged with the software.

“We have clear evidence of these additional violations,” said Cynthia Giles, an official with the EPA’s Enforcement and Compliance Assurance office.

VW has once again failed its obligation to comply with the law that protects clean air for all Americans.

In a statement from its headquarters in Wolfsburg, Germany, the company denied its 3.0 litre engines had defeat devices.

“The United States Environmental Protection Agency informed Volkswagen Aktiengesellschaft on Monday that vehicles with V6 TDI engines had a software function which had not been adequately described in the application process. Volkswagen AG wishes to emphasise that no software has been installed in the 3-liter V6 diesel power units to alter emissions characteristics in a forbidden manner.”

Volkswagen will cooperate fully with the EPA clarify this matter in its entirety.

Separately Porsche, a VW unit and directly caught up in the controversy for the first time, said: “We are surprised to learn this information. Until this notice, all of our information was that the Porsche Cayenne Diesel is fully compliant.”

A Volkswagen Passat CC car undergoing testing for its exhaust emissions John Stillwell / PA Wire/Press Association Images John Stillwell / PA Wire/Press Association Images / PA Wire/Press Association Images

The new notice covers about 10,000 mostly luxury cars already sold in the United States, and an unknown number still unsold.

But, as with the initial notice, it was possible that the same cars sold elsewhere would be shown to have software defeat devices as well.

The software makes the engines run according to US standards when emissions testing is ongoing.

“At exactly one second” after the emission test ends, Giles said, the software switches into standard-drive mode in which poisonous nitrogen oxide emissions rise to up to nine times the EPA standard.

The expansion of the scandal spelled further damage to Volkswagen, the world’s second-largest automaker and long an emblem of Germany’s industrial might.

Already one chief executive of the company, Martin Winterkorn, has lost his job, and shares of the giant have lost nearly one-third of their value since the scandal erupted.

Martin Winterkorn Markus Schreiber / PA Wire Markus Schreiber / PA Wire / PA Wire

The new US notice of violation, for the larger-engined cars, could weigh on Winterkorn’s replacement, Matthias Mueller, who was elevated from running VW’s Porsche subsidiary. At the time of his promotion, Porsche vehicles were not known to have the defeat devices.

Moreover, the first notice of violation on September 18, which launched the scandal, made clear that from the EPA alone, the company was facing a potential $18 billion (€16bn) in fines, based on the maximum allowed per vehicle and the half-million US-sold cars covered.

There are also a number of owner lawsuits against the company, and it could be hit with fines in other countries and regions as well.

- © AFP, 2015

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