I was referring to the intake filter only. My previous stock filter was dirty and found the AFE filter which I have used on previous cars with good results. There are good number of members here that use them and the engine breathed better with it. I do not know about an AFe intake for the X5 and I do not have one. Can you explain what you are referring to?

My tuner believes it is related to the EGR and recommends an EGR bypass. I have also received another recommendation from another reputable shop not in my area that this is related to either the injector or mass air flow filter.