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France may have protected Renault in diesel emission probe

24 August 2016

The official report from the French inquiry known as Commission Royal, after the minister in charge of the investigation Ségolène Royal, has omitted significant details about the test results of Renault diesel cars, according to an article published in the Financial Times. The withdrawn information suggests that a diesel model by Renault was programmed to detect if the vehicle was subjected to the regulatory emission test and to produce lower emission during the regulatory test procedure—a test cycle beating strategy similar to that used by Volkswagen.

The Commission Royal report published at the end of July summarized the results of a 10-month investigation by the French environment ministry, following the Volkswagen diesel emission scandal. The investigation found that about a third of the 86 diesel vehicles that were tested emitted higher levels of NOx on the road, compared to tests over the regulatory NEDC test. The worst offender in the French inquiry was the Fiat 500X, which emitted 1,354 mg of NOx per km on the road, compared to 68.2 mg/km over the NEDC. The legal Euro 6 NEDC NOx limit is 80 mg/km. The list of offending vehicles also included Volvo V40, Renault Talisman and Espace models, Nissan Qashqai, Ford Kuga, Opel Astra and Mokka.

While several vehicles produced increased NOx levels on the road—a phenomenon widely documented and known for a number of years—the investigation found no evidence that any of the carmakers used Volkswagen-style “defeat devices”—software designed to detect when the vehicle is tested and to switch to a low emission control strategy during the regulatory emission test. “The commission cannot, therefore, make any definitive statement on the presence or absence of ‘cheating’ software in the vehicles tested,” said the report.

However, three of the 17 members of the commission revealed to the Financial Times that the published report did not include the full details of their findings, including irregularities discovered in the NOx adsorber regeneration in the Renault Captur. The decision not to disclose the information could have been linked to the 20% stake in Renault owned by the government.

The Renault Captur’s NOx adsorber (trap) was found to regenerate five times in rapid succession at the end of the prescribed test preparation procedure, a behavior that was not seen during road driving. The regenerated NOx adsorber allowed the car to produce much lower NOx emissions during the NEDC procedure. “We can’t be sure that Renault’s software detected the test per se, but it seems that Renault has optimized the NOx trap to target this very specific set of conditions,” one commission member was quoted to say.

Members of the commission were also concerned that Renault’s cars had been programmed to shut off EGR once air temperatures under the hood exceeded 35°C, a temperature that is frequently surpassed during normal driving. Renault implicitly admitted that the temperature cut-off was unnecessary by agreeing to recall models to recalibrate it through a software update.

While Renault denied using software to cheat emissions testing, the company recalled 15,000 vehicles in January and has agreed to implement more robust emission control technologies as part of a wider action plan.

The lenient approach to carmakers in the aftermath of the VW scandal seems to be typical for most EU authorities and Member States. Nearly all of the VW penalties and responsibilities for their emission cheating can be linked to legal actions in the United States, a market where only about 5% of the offending vehicles were sold. In Europe, on the other hand, Volkswagen actions have not yet been found to be illegal or to violate any of the EU emission regulations.

Source: Financial Times


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