In a news conference detailing the latest developments in the investigation into the affair, VW supervisory board chief Hans Dieter Poetsch and chief executive Matthias Mueller said evidence suggested the scam was the work of just a small group of engineers.
There was "no evidence to suggest that supervisory board members or management board members are implicated," Poetsch said.
VW was plunged into its deepest-ever scandal in September, when it was forced to admit it had installed emission-cheating software into 11 million diesel engines worldwide.
VW, once seen as the paragon of German industry, is facing still incalculable costs, not only to its reputation and global sales and profits, but also potential billions in possible fines and legal costs.
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CEO Mueller, brought in to resolve the crisis, said VW was "currently doing everything it can to limit the effect the current situation has on its business performance."
The group's operating business "is meeting expectations, and the 2015 annual forecast, which was updated at the end of October, remains unchanged," the 62-year-old executive said.
"Although the current situation is serious, this company will not be broken by it," he insisted.
It was effectively Mueller's first news conference in person as CEO, aside from a telephone conference at the end of October, where he revealed that VW had run up its first quarterly loss in 15 years as a result of the billions of euros it set aside to cover the costs of the scandal.
VW, which had looked set to overtake Toyota this year as the world's biggest carmaker in terms of sales, confessed to systematically fitting so-called defeat devices into its diesel cars in order to meet the rigorous emission standards in the US.