Presume this is a diesel? What age is it? The early engine (Pre 2011) EGR valve is about £350 from Peugeot - but you can get a proper Valeo one for around £100 on the likes of E-bay. Fitting it looks like a nightmare as it is buried down the back of the engine, but once you get into it is not as hard as it looks. It should only be a couple of hours labour - which makes the price from Pug look excessive - ask them for a breakdown. In order to do it, you need to remove both the air and fuel filters, so if these have not been replaced recently, then I would get new ones fitted - there will be no labour cost involved (but the fuel filter is pricey, particularly if you buy a Peugeot one!).

Let me know if it's a later car, and I'll look up the price for the EGR valve for that - I think it's more complex, and more difficult to fit.

Hi I have had the same issue, I took my 1.6L petrol 2009 peugeot 308 2009 plate to the dealership. The said It is the turbp so i got it replaced. Cost me around £1000 and it didnt solve the problem. I have taken it to a local garage they have put it on the diagnostics and have got some codes relating to cylinder misfires. They reckon it is the timing chain. He said the timing chain dictates when the engines valvues should open and close, hence the emission value isn't opening because the chain is taught so the emissions cannot escape (something along these lines). The anti polussion system faulty message is a real headache because I cannot drive the car due to the loss of power. Has anyone solves this porblem.

Thanks In Advance.