text: I can't say that I'm the faintest bit surprised by this.  While Volkswagen was perhaps the most egregious example, I would be shocked if they were the only one to try such a thing.
  
  The reality is that diesel engines tend not to burn very cleanly, especially smaller diesel engines in small cars where there isn't much room for pollution control mechanisms.  Customers buy diesels for their low fuel consumption rates and putting those pollution controls in works against fuel consumption, so there is a strong incentive for manufacturers to "cheat" the rules, polluting too much in order to get better fuel consumption.
  
  We'll see what comes of this but I'm certain VW wasn't the end of the story, and indeed Renault and Fiat probably aren't the end of it either.