Nissan Serena 2006 problem

Hello friends. I need your help I have Nissan Serena, in the scanner it gives the code P0403 malfunction Egr. But I already changed the solenoid valve and continues to persist the fault check the wiring the wiring the gase recirculation canyraries and nothing and please if someone could facilitate the manual we could exchange for other manuals of any brand. The engine is MR20 please help me thanks