The latest EcoTest results published by the ADAC – Europe’s largest motoring club – confirm that majority of modern diesel cars emit significantly more toxic nitrogen oxide (NOx) pollution than officially permitted.

Nitrogen oxide is a harmful pollutant that is often blamed for damaging the environment and has also been proven to have serious health implications.

Under the current Euro 6 standard, the maximum level for NOx in diesel vehicles is 80mg/km.

“The ADAC EcoTest shows that virtually all manufacturers have a massive emission problem with their diesel engines” said Thomas Burkhardt, ADAC Vice President of Technology. Out of the 188 tested vehicles, only 6 met the official legal limit of 80mg of nitrogen oxide per kilometre.

The clear winner of this test is Mercedes Benz E 220d 9G-Tronic emitting only 24mg/km, thanks to AdBlue technology. The worst performing vehicle was Renault Trafic Combi emitting 1024 milligrams of nitrogen oxide per kilometre.

Place Make and Model NOx Emissions mg/km
 1  Mercedes-Benz E 220d 9G-Tronic 24
 2  BMW 520d Luxury Line Steptronic  53
 3  BMW 118d Urban Line Steptronic  69
 5  Opel/Vauxhall Zafira 2.0 CDTI ecoFlex  76
 5  Seat Ateca 2.0 TDI 4Drive DSG  76
 6  BMW 730d Steptronic  80
 7  VW Passat Variant 2.0 TDI SCR BMT  84
 8  VW Sharan 2.0 TDI SCR BMT  88
 9  Mercedes GLC Coupé 250d 4Matic 9G-Tronic  99
 10  Mini Cooper D Countryman 107

Source: ADAC

The ADAC then averaged their test results for each manufacturer group. The vehicles with the lowest NOx emissions came from BMW (including Mini), followed closely by Volkswagen (VW, Audi, Skoda, Seat) and Mercedes-Benz.  The most NOx polluting vehicles came from Renault/Dacia.

The vehicles with the lowest NOx emissions came from BMW (including Mini), followed closely by Volkswagen (VW, Audi, Skoda, Seat) and Mercedes-Benz.  The most NOx polluting vehicles came from Renault/Dacia. On average, Renault/Dacia vehicles emit around four times more nitrogen oxide than BMW/Mini, 141mg/km vs 684mg/km.

ADAC EcoTest: Average Nitrogen Oxide Emissions by Car Manufacturer

ADAC Test: Average Nitrogen Oxide emissions by car manufacturer
Source: ADAC