Diesels illegally pumping out pollutants after garages remove filters designed to cut emissions

Tens of thousands of diesel cars are illegally pumping out dangerous pollutants because unscrupulous garages have removed exhaust filters designed to cut emissions of deadly particulates.

Air pollution from diesel particulates has been linked to 29,000 deaths a year. Despite a government crackdown last year, backstreet garages and tuning shops are still advertising services to remove factory-fitted diesel particulate filters (DPFs) and reprogramme on-board computers to allow cars to be serviced more cheaply, deliver more power and trick emissions-testing equipment.

open image in gallery

Diesel particulates enter the lungs and bloodstream; they have been shown to stunt children’s brains, and have been linked to autism, heart disease and cancer. Labour has joined air quality campaigners to accuse the Government of “negligence” over air quality regulation.

In the wake of the VW scandal – which centres on nitrogen oxides rather than particulates – testing authorities across Europe have been focusing on diesel engines. Last week, police in Spain raided eight garages in Madrid after a tip-off that they were removing DPFs and reprogramming software. However, in the UK, a legal loophole allows garages to remove the devices without fear of prosecution. An Independent on Sunday investigation has found that more than 1,000 garages, backstreet mechanics, and tuning firms are offering this service, often for as little as £250. It is only an offence to drive a car without a factory-fitted DPF.

The filter has been mandatory on any new diesel vehicle since 2009, but can become blocked after 80,000 miles and can cost up to £1,500 to replace. Last year, the Government introduced new rules so that a car should not pass its MOT if the filter has been removed; however, many garages reportedly fail to inform customers of this, while others openly boast that their work won’t be spotted during an MOT test.

“This will add to growing public concern about pollution from diesel cars, and the impact on air quality,” said Kerry McCarthy the Shadow Environment Secretary. “Air quality regulations exist to protect public health, but we are being let down by a negligent Government that is failing to enforce them.”

The revelation that thousands of drivers are still flouting the law by having their DPF removed and accompanying software altered has dismayed clean air campaigners. Simon Birkett, director of Clean Air in London, said the scale of DPF removal uncovered was “shocking”.

open image in gallery

“Frankly, at least VW had a chip, even if it cheated during testing. Removing factory-fitted DPFs involves tricking or disengaging the whole emissions chip, all the time, on gases and particles,” he said.

Chris Roberts, managing director of Quantum Tuning, which provides DPF deletion-capable software to more than 280 garages and tuning firms, said garages were responding to “demand” from customers who “don’t have the money to spend on a £1,500 new filter for a car that might be worth £2,000”. He said: “Either they scrap the car or get something done about it. And if they are going to have it done, they may as well have it done properly by a garage that will explain what the MOT implications are, as our dealers do.” Mr Roberts said many customers viewed driving without a DPF as comparable to a minor speeding offence.

Campaigners say the MOT fails to catch DPF removal because it only includes a “visual inspection” of the hardware – which is often welded back together – and an “optical smoke test” which cannot detect dangerous particulate matter. A Department for Transport spokesman said: “If a car is fitted with a DPF and it is removed, it is illegal to be driven on the road. We continue to monitor how many vehicles are failing the MOT for this reason, and explore steps to stamp out this practice.”