European Exhaust and Catalyst
European Exhaust and Catalyst
Common DPF Misconceptions – Why Not Just Take The DPF Off?
Published on: 22/05/2019

All this fuss for the DPF, why not just take it off? Regular DPF problems may frustrate some drivers so much so that they may consider removing the filter entirely. Incredulously, this is actually sometimes encouraged by firms who advertise their services on the web for DPF removal or ‘DPF Delete’ options.

They flout half truths stating that it is not illegal to remove the DPF, and that the vehicle will still pass MOT smoke opacity tests without it.

Thankfully for the vendors, it’s not actually illegal for them to carry out DPF removal work. Unfortunately however, as the driver, it would be illegal for you to drive said vehicle on public roads.

In legal terms, it is an offence under the Road Vehicles (Construction & Use) Regulations (Regulation 61a (3)) to use a vehicle which has been modified in such a way that it no longer complies with the air pollutant emissions standards that it was designed to meet.

When a DPF is removed, it will almost always result in this legal requirement being broken.

The Department for Transport has issued guidance clarifying this. If you’re MOT savvy, you might already know that current emissions tests carried out as part of a standard MOT are not sensitive enough to show whether a DPF is fitted. It is therefore irrelevant that a smoke opacity test may be passed without one; DPFs are designed to produce much cleaner exhaust emissions than that. What you might not know, is that since February 2014, a visual check of the exhaust system has been required as part of the MOT test. If this visual check should find that a DPF is missing where there should be one, the vehicle will automatically fail the MOT.