PARIS – Renault has used “fraudulent strategies” for over 25 years to cheat on pollution tests for diesel and petrol engines with the knowledge of top management, according to a report by French fraud investigators obtained on Wednesday by AFP.
“The entire chain of management” of the French car maker up to its chief executive Carlos Ghosn were implicated in the suspected fraud, added the report, which led prosecutors to open a probe into Renault in January.
Police suspect the automobile maker of having put in place the fraudulent strategies “with the objective of creating false results for antipollution tests”, in order to be seen to be complying with regulatory norms.
The document, the existence of which was first revealed by the Liberation daily, concentrates on recent car models, but the fraud investigators – helped by statements by a former Renault employee – estimate that questionable practices have been in place since 1990.
The first generation Renault Clio, which came out in 1990, is believed to be one of the models involved.
The alleged fraudulent practice recalls the so-called “dieselgate” scandal involving Germany’s Volkswagen which admitted in late 2015 to installing so-called “defeat devices” into 11 million diesel vehicles worldwide, designed to reduce emissions of harmful nitrogen oxides while the engines were undergoing regulatory tests.
Besides Volkswagen (VW), Renault is the only carmaker so far to be referred for possible criminal investigation in France over suspected breaches of emissions rules.
Following VW’s exposure for using software to cheat US tests, Renault and others have attracted scrutiny for their own use of “defeat devices” that reduce the effectiveness of technology to purge toxic nitrogen oxides (NOx) from exhaust.
Such devices are calibrated to meet pollution standards during regulatory tests but not in many other conditions encountered on the road, when real emissions are allowed to soar. They are illegal except when deemed necessary to protect the engine – a European loophole that has been widely exploited.
Carmakers including Renault, Opel and Fiat told a separate French investigating committee earlier this year that defeat devices in their vehicles were legal under the exemption. But the panel concluded their technical justifications “remained to be proven”.
Renault had explained the NOx-cutting exhaust gas recirculation (EGR) in its top-selling diesel engines had been found to cause serious turbo clogging problems.
Engineers responded by programming the EGR to shut down outside a narrow “thermal window” of air intake temperatures, 17-35ºC. While passing regulatory tests carried out at room temperature over short periods, the protocol sends NOx emissions sky-high on the road.
Other unidentified carmakers remain under investigation by the DGCCRF agency, the government said in its statement.