Stoke-on-Trent garages 'illegally remove car emissions filters'
Car filters designed to stop harmful emissions escaping from diesel cars are being illegally removed by garages in Stoke-on-Trent and Staffordshire.
Out of ten garages approached by undercover reporters from BBC's Inside Out, five were prepared to take off the diesel particulate filter.
Short journeys can cause the filter (DPF) to clog up and stop the car running properly.
Trading standards spokesman Brandon Cook said their removal "was terrible".
The filter can cost thousands to replace so some garages are offering to remove them instead, the investigation showed.
"It's just a flagrant breach, there's no way that's right," said Mr Cook.
Diesel soot emissions are harmful to the environment and since February, any car that has had its filter removed should fail its MOT test.
But one garage exposed by the programme was able to get around the problem by removing the filter but replacing the empty container so an MOT tester would not spot it.
Mr Cook said: "The fact you can get away with it doesn't make it right - what you've come up with here is some flagrant breaches that need investigating - there's clear evidence there that what they're doing is illegal."
He said both the consumer and the garage was at fault and added: "These garages need to know they can't get away with this… this isn't something they can just do because it's difficult to detect. Someone needs to make sure these things can't be tampered with."
A Department of Transport statement said all MOT garages would be notified on 26 October they risk losing the authorisation to perform MoT tests if they offer to remove the filters.
"We welcome any information gathered by Inside Out on garages offering DPF removal so these cases can be investigated," the statement said.