Volkswagen AG is the largest European carmaker and the biggest by sales in the world after the first six months of the year, and its admission on cheating on diesel emissions tests could have bigger long-term consequences on its continental rivals. Just a little over two weeks ago German automaker VW AG admitted it had rigged diesel emissions tests in the US and later on said it had installed the cheating software on 11 million autos in the world, with German authorities also claiming foul play on the European continent.