FAP/DPF, EGR, cat-delete: what does French law actually say?

DPF, EGR, catalytic converter: these parts exist to cut down engine pollution, but they're also a frequent source of expensive faults — especially on cars doing a lot of short, urban trips. Plenty of drivers consider a software delete, but few actually know the legal picture.

What the regulations say

In France, these components are mandatory on any vehicle used on public roads. Removing or disabling them makes the car non-compliant with its original type approval, which can lead to:

• failing the mandatory roadworthiness test (recent inspection procedures now specifically check that these components are present and working),
• penalties during a roadside check, since the modification can be treated as making the vehicle non-compliant.

Rules in this area change fairly often — if you're unsure, the most reliable source is always the current official regulations, not a blog post, however carefully written.

The context where these services still apply

The FAP/DPF, EGR and cat-delete solutions we offer are strictly for off-road, non-public-highway use: competition vehicles, track-only use, export to a country with different regulations, or any other properly supervised use outside the open road network. We flag this clearly before any work starts.

Our position

We provide the technical know-how; how the vehicle is then used remains the owner's responsibility. If your real goal is fixing a recurring DPF or EGR fault on a car that stays on public roads, diagnosis and repair is usually the better path than a delete — a DPF that keeps clogging up is often hiding an underlying mechanical issue that's worth fixing at the source.

Need a diagnosis before deciding? Check out our ECU repair service, which includes a full diagnosis of this type of fault.