Just like manipulating any other part of the emissions system It is illegal to remove / gut or change the DPF system
in any way and carries a £1,000 fine for consumers and £2,500 for light good vehicles. So, yes it is an immediate MOT
failure if caught doing so. Reference: https://www.gov.uk/…/diesel…/diesel-particulate-filters Sanctions are a lot
more serious for Heavy Goods Vehicles. Our advice is to diagnose correctly, resolve the cause of DPF issues
and if required clean or worst case replace the DPF to stay legal, after all, if you don’t put the above
aside you’ll still likely to have an underlying fault that will almost certainly lead to other issues.