Theft and security
Catalytic converter stolen? What to do next
A sudden roar when you start the engine usually means the catalytic converter has been stolen. What to do next, and how to stop it happening again.
Blog
Practical articles on catalytic converters, DPFs and GPFs, MOT emissions and choosing the right part for your vehicle.
DPFs and GPFs
What is a GPF? Petrol particulate filters explained
A GPF is the petrol version of a DPF. What it does, why direct-injection petrol engines have one, how to tell if yours does, and the law on…
Buying guides
How much does a replacement catalytic converter or DPF cost?
Typical UK prices for a replacement catalytic converter, DPF or combined unit, from our own catalogue, and what makes the price go up or down.
Looking for the basics? Our Help & Advice guides cover how catalytic converters and DPFs work, fitting, the law and warranty.