The settlement would be the largest ever automotive buyback offer in U.S. history and most expensive auto industry scandal.
The government has vowed to punish executives for corporate wrongdoing. Will it follow through?
More Volkswagen, Audi and Porsche owners could face recalls of their cars.
The troubled carmaker suspects the camshaft lobe may shear off reducing engine and brake power.
Among the diesel models officials named as being in violation of U.S. laws are the Porsche Cayenne sport utility vehicle and five Audi models.