Unless the garage you took it to had Diagbox I would get a second opinion.
How to: Find and get a Planet / Diagbox Diagnostic
If you've signed up to this forum for help with your Peugeot (don't worry, most people do!), then you'll probably be recommended to get a "Peugeot Planet" diagnostic before proceeding. The reason for this is because some faults could be caused a number of different things - the "anti pollution...