Is DPF removal Illegal?

https://www.carmagazine.co.uk/car-news/motoring-issues/illegal-exhaust-modifications/

Link Above

The landscape for vehicle modifications in the UK faces a seismic shift following a groundbreaking court ruling that could render certain modifications illegal. The Driver and Vehicle Standards Agency (DVSA) recently made a landmark move by prosecuting an aftermarket tuner for modifying a car with a decat exhaust and a ‘pop bang’ ECU remap.

The DVSA’s Market Surveillance Unit engaged the firm to fit a decat pipe and pop and bang remap on a Ford Fiesta ST.

Upon completion, the DVSA discovered the critical alteration: the Fiesta’s catalytic converter had been replaced with a pipe, linking the front and rear sections of the exhaust. This modification increased the car’s emissions, which was immediately flagged as a potential MOT failure.

The ECU remap proved equally problematic, retarding the ignition and prompting an abnormal increase in fuel flow during off-throttle moments, creating the notorious ‘pop bang’ effect. This alteration propelled the Fiesta’s drive-by noise emissions to 77dB, surpassing the legal limit by 2dB. To put this in perspective, a mere 1dB increment represents a doubling of noise volume.

What stirred further concern was the firm did not warn of the modifications’ illegality, as noted by the DVSA. Consequently, in a groundbreaking case, the tuner was found guilty of ‘fitting an unsuitable vehicle part and rendering the vehicle illegal for road use.’ The repercussions were substantial, with the Magistrates Court imposing fines and costs totalling £7,234. The magistrates emphasised the obligation of business owners to comprehend and adhere to the law.

This case sets a precedent, potentially prompting tuning companies to reconsider offering ‘pop bang’ remaps. 

The legal ramifications extend beyond the tuning companies. The Department for Transport is currently trialling ‘noise cameras’ designed to detect vehicles surpassing legal noise limits. The Police could issue a £50 on-the-spot fine to drivers of such vehicles. If successful, these noise cameras could soon blanket the UK’s roadways.

The DVSA’s report indicates their commitment to ongoing investigations into defective or unsuitable vehicle parts, a commitment slated to continue throughout 2024.

In an attempt to discover how easy it could be to prove a diesel vehicle has been modified in such a way as to render the vehicle illegal for road use, Gotboost has developed a NOx sensor.

The portable device made from various components for less than £1000 is capable of checking EGR and AdBlue deletes in seconds.

If the DVSA commitment to investigate unsuitable parts and remaps that increase emissions is to continue then it is possible that increased scrutiny of diesel exhaust emissions may feature in any upcoming MOT changes.

Gotboost has proved that it is possible to measure NOx emissions at the tailpipe using low-cost detection methods.

Be warned!