Over in Europe, Diesel engines are quite popular. But, Euro 6 emissions standards are getting tougher and, starting in 2019, emissions performance tests for new cars will be based on real driving scenarios. This means that manufacturers ultimately have to spend more to treat emission systems. And, according to a report from Reuters, Renault is rethinking its investment in diesel altogether. In fact, Renault is expecting diesel engines to disappear from most of its European-market cars due to the ever increasing cost of emissions equipment.