Results of testing on a Euro 6 BMW 320d diesel by the German environmental organization Deutsche Umwelthilfe (DUH), ZDF’s WISO and a software expert point to the use of inadmissible defeat devices, according to DUH. The organizations found that road-testing NOx emissions are up to 7.2 times higher than those produced on the dyno, which met the official NOx limit. The main cause for the higher on-road values is that the exhaust gas recirculation (EGR) is in some cases practically switched off under certain conditions, DUH said.
According to the investigation, not only the speed, but also the torque is used as a parameter for this shutdown. The software expert Lothar Daub explained that EGR is switched off above 3,500 rpm; this configuration was stored in the software of the vehicle, with a a map and corresponding data. Such a speed is reached at 47 km/h in second gear, 70km/h in third gear, 87 km/h in fourth gear and 112 km/h in fifth gear.
The European Type Approval Regulation 715/2007 explicitly includes in its definition of “defeat devices” the engine speed (RPM) as a parameter for reducing the effectiveness of the emission control system during normal vehicle operation. General activation of defeat devices is inadmissible under this regulation.
DUH noted that on 27 September 2017, Harald Krüger, CEO of the BMW Group, said: “We did not manipulate the vehicles, we have clean diesel, and they are the best in the world, there is no defeat device at the BMW Group.” This full-bodied promise is in clear contradiction to the results of the exhaust and software investigations of the BMW 320d, DUH charged.
The available measurement results are very clear indications that inadmissible defeat devices are present in the engine control software. These must be completely removed. The vehicle must have fully functional exhaust gas cleaning in all normal operating situations. Today we will hand over our investigation results to the responsible authorities and demand a review and, if necessary, revocation of the type approval and an official recall for all vehicles which have an illegal defeat device.—Jürgen Resch, DUH General Manager
The DUH is applying to the German Ministry of Transport for the publication of all officially known defeat devices for diesel passenger cars from different manufacturers; these previously had been refused based on the protection of trade secrets of the manufacturers.
The vehicle was tested by TÜV Nord on the dyno using the New European Driving Cycle (NEDC). The vehicle achieved a very good result with 27.6 mg NOx/km. Even when driving on the test bench with 10% higher speed (NEDC + 10%), the values were well below the Euro 6 limit.
The same vehicle was then measured on the road. The Real Drive Emissions (RDE) emissions were well above the Euro 6 limits. Particularly in the out-of-town component of the cycle, NOx emissions were significantly increased—and even higher in the NEDC + 10%.
The DUH has sent its measurement reports to the Federal Ministry of Transport and the Federal Motor Transport Authority (Kraftfahrt-Bundesamt) and has requested that this matter be clarified. DUH suggested that BMW can not argue that the settings are to protect the engine, because the vehicle does not show this exhaust behavior on the test bench.