Diesel cars are pumping out nine times the limit for harmful emissions
DIESEL cars on British roads can emit more than nine times the level of dangerous pollutants allowed in official tests.
The figures come from research by consumer group Which?, whose experts tested 278 diesels between 2012 and 2016.
It said the problem is widespread, but there were particular issues with the Jeep, Renault and Nissan vehicles.
The EU sets limits for emissions of nitrous oxide (NOx) during tests on cars before they are allowed on the road.
NOx pollution on roads is associated with tens of thousands of early deaths every year in the UK. Such is the concern for public health that some campaigners are calling for diesel engines to be banned.
VW has been in the dock around the world for fitting ‘defeat devices’ which cheated official emissions tests to make NOx levels look low.
But it is clear from the Which? figures that virtually all the major manufacturers are responsible for selling cars that emit much higher levels of pollutants in ‘real world’ driving conditions. The EU has tightened the emission levels permitted by new cars six times since 1993 to protect public health.
The NOx standard introduced in 2011 as part of the Euro 5 regime was set at 0.18grams per kilometre(g/km). It was tightened to 0.08g/km under the Euro 6 limits introduced in 2015 and covers vehicles sold since then.
All the cars tested by Which? met the required standards during offi- cial examinations. But there is no legal requirement to hit these levels once the cars are on the road. Eleven older diesel Renault cars tested by Which? had NOx emissions that were an average of four times higher than the Euro 5 limit. Five more modern ones, sold since 2015, had NOx levels that were an average of nine times the Euro 6 limit. The Renault Grand Scenic 1.6 dCi 130 produced 0.73g/ km of NOx. Six Nissan cars with Euro 5 diesel engines had average NOx emissions that were 4.4 times the limit allowed in official tests.
Jeep produced some of the highest emissions. Two of its older models were emitting an average 1.74g/km of NOx, which is nineand-a-half times the Euro 5 limit they met in official tests.
Which? tested 31 BMW cars, which had some of the lowest ‘real world’ NOx emissions for diesels.
The average for BMWs was 0.41g/ km, which is 2.3 times the test limit for Euro 5 cars. More modern BMWs had an average of 0.14g/km – 1.75 times the Euro 6 standard.
New tests to assess ‘real driving emissions’ and car performance will be introduced in September.
Renault said all its vehicles conform to current standards. It said: ‘Since mid-2015, Groupe Renault has committed to improve the performance of its anti-pollution systems. The vehicles tested by Which? would not have benefited from this improvement plan.’
Nissan said: ‘All our vehicles sold in Europe meet the Euro 5/6 emission standards. This [Which?] report shows significant variances for most brands tested.’
Jeep failed to give a response.