Renault and Jeep are worst offenders for real-world diesel emissions, says report

Renault and Jeep diesel engines emit far higher levels of nitrous oxide than permitted, new real-world testing has found.

Analysis of 278 Euro 5- and Euro 6-compliant diesel cars found that, on average, diesels are “cleaner than ever”. However, all 16 diesel Renault cars that were tested were found to be well above official NOx limits, while Jeep “almost broke the scale”.

Independent consumer magazine Which? also found that Renault’s more modern Euro 6 engines were, on average, worse than the Euro 5 averages of other carmakers. Dacia, which is owned by Renault, also had “comparably high” emissions.

In response, Renault said: “All Renault and Dacia vehicles are, and always have been, homologated in accordance with the laws and regulations for all the countries in which they are sold. They all conform to the current standards.

“However, Groupe Renault has been aware that there remains significant potential for improvement regarding the release of NOx in real-use conditions.

“Since mid-2015, the company has committed to improve the performance of its anti-pollution systems with the objective of reducing the gap between real driving emissions and standards-based emissions.”

Jeep also performed poorly in the test. Just two of its Euro 5 engines were investigated and were an average of nine and a half times over the limit they achieved in official test conditions.

By contrast, BMW, Mini and Toyota received good results, with some of the lowest NOx emissions readings of any of the diesel cars.

Richard Headland, Which? magazine editor, said: “While our tests show that some car manufacturers are making progress on reducing the amount of toxic emissions from their models, many have a long way to go in cleaning up their act.

“We hope that the improved official tests being brought in later this year will more clearly name and shame those manufacturers that are failing to meet their obligation to lower emissions.”