Matters of Testing Update

Diesel Particulate Filters: Protecting the Environment and the MOT’s Integrity

Since February 2014, when an MOT tester inspects a diesel vehicle’s exhaust system they have to check if there’s a diesel particulate filter. Diesel particulate filters are important in maintaining acceptable levels of air quality.

Cited from: Diesel particulate filters: protecting the environment and the MOT’s integrity

The DPF is a vital component that is designed to enable cars to pass the increasingly tough emissions legislation; its job is to trap the particles that are caused by the compression-ignition combustion process in order to prevent harmful smoke from being pumped into the atmosphere. The DPF is vital in maintaining acceptable levels of air quality.

The law has been that since 2014, when a tester inspect a diesel vehicle’s exhaust, they have to check that there is a DPF. They’ve been used for more than 20 years and have been fitted on diesel vehicles since 2013. Some people believe that removing the diesel particulate filter would improve both the performance and the cost. It is illegal to drive a vehicle that’s been modified in that way.

Some garages believe that removing a vehicle’s DPF will improve it’s performance and make it more economical to run. Another reason that a garage may remove it is that they believe it is more cost efficient to remove the particulate filter than replacing an old blocked up filter with a new one.

The DVSA recently investigated 2 linked companies who were offering to remove diesel particulate filters from vehicles, describing their services as being “MOT friendly” and “hard to notice”.

These two companies were both found to be run by authorised testers. The testers were banned from conducting MOT tests for 2 years and the owner of the station was banned for 28 days.

MOT Testing Guide, appendix 8.1 ‘Cessation Without Previous Warning’ states:

(Single Offence Cessation) 

Other serious cases of loss of good repute. This provision will be used only in serious cases where urgent action is essential to preserve the integrity of the MOT Service;

Evidence that the AE or the AE’s agent has been involved in criminal activity or A reputable source of intelligence brings into question the good repute of the AE or operation of the VTS (500 points).

Click here to view the MOT Testing Guide

Actively taking part in the removal of a diesel particulate filter or passing a vehicle that needs a DPF is commiting fraud. It goes against everything the MOT stands for. As an MOT tester, you are at the forefront of making sure the MOT’s integrity is maintained.

Why not book your MOT Tester Course (Award in MOT Testing Class 4 & 7)?

We also offer an Award in MOT Test Centre Management. Not only will we teach you how to pass your exam, we will guide you on how to run your very own MOT station.

Call us on 0345 459 0231 or email to book your course or find out more!

MOT Centre Management
MOT Centre Management

Recognised by DVSA, this detailed course will develop your understanding of how to run a vehicle testing station (VTS).

Award in MOT Testing Class 4 & 7
Award in MOT Testing Class 4 & 7

This intensive course will develop your skills around the MOT Testing Routine to help you become a Tester for class 4 & 7.