The AZ guy is on drugs, see if he'll sell you some
No such thing as a master engine filter. He might be referring to the EGR valve, who knows. IF that's the problem, there's a replacement gasket for the EGR valve that has a screen built into it that's designed to break up the carbon chunks so they don't interfere with the EGR valve operation. Best to start a new thread for the other problems though.