Diesel cars are being set up to foil emissions tests, by selectively cutting emissions when the car’s central computer recognises conditions similar to those used in official tests, scientists have found.
A new investigation, carried out by Dutch technical consultancy TNO, has found that new cars are being programmed to temporarily slash the amount of pollutants emitted when under test-like conditions to meet new European standards, the Sunday Times reports.
Many car buyers have ditched their petrol cars and replaced them with diesels as CO2 emissions-based road tax pushes motorists towards cheaper-to-tax diesels. However, while diesels typically emit less CO2, they emit more of other pollutants including nitrogen oxides, raising concerns over their environmental impact.
The engine management systems perform differently in test-like conditions compared with driving on the road.
Furthermore, when driven on the road, the amount of pollutants emitted by diesels spirals, in some cases rising to 10 times the legal limit. Gerrit Kadijk, who was involved with the TNO report, said: “The engine management systems perform differently in test-like conditions compared with driving on the road.
“It is not illegal – they follow the letter of the law but not the spirit. On-board computers can easily be programmed to identify such test “signatures”.
The benefit of this according to Kadijk is that: “It means they can make selective use of emission-reducing technology, rather than having it on all the time, and that saves manufacturing costs – a big deal for them.”
This is the latest blow to diesel owners, after Boris Johnson called for diesel models over a year old to be scrapped, no doubt infuriating those drivers who switched to diesels on the premise that they are kinder to the environment.
Picture: il fede