Volkswagen (VOWG_p.DE) on Tuesday said it had understated the fuel consumption of 800,000 cars sold in Europe, while majority stakeholder Porsche Automobil Holding SE (PSHG_p.DE) warned that VW’s latest findings could further weigh on its results. The latest revelation about fuel economy and carbon dioxide emissions, which Germany’s largest automaker said represented a roughly 2 billion euro ($2.19 billion) economic risk, deepened the crisis at VW.