*"under the Construction and Use Regulations (more specifically, Regulation 61A of the Road Vehicles (Construction and Use) Regulations) it is illegal to use a vehicle on the road if it has been modified in such a way that it no longer meets the air quality emissions standards that it had to when originally produced."*

This may be so. But as far as re-mapping is concerned this is academic. Unless detailed examination is taken of the software contained within the ECU and the vehicle passes the MOT smoke test, no-one apart from the parties concerned will know that the vehicle has been re-mapped.

The same applies to DPF removal. If the DPF contents have been removed, then unless the MOT tester removes the DPF for inspection or a soot test is implemented, then again no-one apart from the parties concerned will be none the wiser.

As has been mentioned earlier in this thread, the DPF system as it stands is not fit for purpose and the ordinary motorist is being penalised accordingly.

Regards

Pete M