Which? has carried out tests on diesel cars analysing 278 diesel cars from leading carmakers between 2012 and 2016 testing average NOx emissions alongside official Euro 5 & more recent Euro 6 limits (set at 0.18g/km & 0.08g/km respectively)

all 16 Renault cars had NOx emissions up to 4 times higher for Euro 5 & 9 times higher for Euro 6 limits – 0.73g/km & 0.72g/km respectively

6 Nissan cars tested had average NOx emissions of 0.8g/km

Jeep also had some of the highest emissions- 1.735 g/km on the 2 cars tested – 9.5 times the Euro 5 limit

the 33 BMW cars tested had some of the lowest NOx emissions – average of 0.41g/km for Euro 5 & 0.14g/km for Euro 6 – John Kiran Motor Trader