peugeot 307cc 20L petrol 2003 model - hello - keidan

hello i have a peugeot 307cc 20L petrol, 2003 model.. it giving me an ( engine anipollution system faulty ) i went to 4 mechanics but none of them can find the way to fix the problem, as they aren t sure which part can be repair!! the fault is p0410....can someone help me pls?? and am i causing more damage if i continue using the car??? one of the mechanics told me to drive as fast as i can on the 3rd gear and even suggest me to add the fuel treatement

peugeot 307cc 20L petrol 2003 model - hello - Avant

Moved to Technical.