Diesel Decaf

Diesels have a reputation for being dirty and smelly, releasing clouds of soot loaded with ash, carbon monoxide, and silicates into the air. But Volkswagen claims TDI Clean Diesels are different, removing over 95% of these harmful particles from their exhaust. But can a diesel really be clean? To find out, the new Touareg TDI squared off against a traditional diesel for an unexpected comparison.