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Aftermarket ‘pop and bang’ exhausts could make your car illegal

In a landmark case, a car tuner has been fined for modifying a vehicle and making it unfit for the road

Exhaust

Following the trial of noise detectors in select regions last year, the UK clampdown on loud exhausts has advanced further in a court case brought by the Driver and Vehicle Standards Agency (DVSA) this month. 

Wakefield-based tuner AET Motorsport was hit with fines and costs totalling £7,234 after Kirklees Magistrates’ Court found the firm guilty of advertising and fitting exhaust components that render vehicles illegal to use on the road. The magistrates remarked that the case is ‘a lesson that any business owner has an obligation to know what the law is’.

Having found AET Motorsport to be openly advertising decat exhaust systems and ECU maps designed to generate more noise, the DVSA’s Market Surveillance Unit carried out an investigation to determine the legality of the services in question. 

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Investigators enlisted AET Motorsport to carry out the work on a Ford Fiesta ST, and upon inspecting the car, the DVSA found that the catalytic converter had been replaced by a link pipe – an immediate MOT failure and increase in emissions. A ‘pop and bang’ engine remap had also been installed; this retards the ignition and reduces fuel cut-off on the overrun, producing loud crackles and pushing exhaust noise beyond the legal limit. The DVSA said that AET Motorsport gave no forewarning of the illegality of the modifications. 

The DVSA describes the case as the first of its kind, and it’s one that could have ramifications for the many other aftermarket firms offering similar services. Speaking on the case, DVSA’s Head of the Market Surveillance Unit said:

‘DVSA’s Market Surveillance Unit ensures vehicles, vehicle parts and vehicle accessories sold in the UK meet required specifications and are safe for people to buy. This investigation shows DVSA takes this activity seriously and we will continue to take strong action on offenders’.

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