PLZZZ HELP!! 99 Isuzu Rodeo 4x4 6cyl. Code P0405

Recently discovered 5 codes in regards to above vehicle(P0102,P0304,P0405,P0452,P0453), the only one Im having problems finding troubleshooting advice to is P0405..the other codes offer possible causes and possible fixes starting cheapest/quickest to more advanced both in price as well as technique. Anyone who can help or has had this problem or can recommend where to start to fix these problems..please help before the rest of my hair is pulled out..lol Thanks in advance for your time and consideration.

Im not sure why you're having the issue with the egr fault out of all the others. In my professional opinion the evap faults would be more involved diagnostic work potentially then an egr fault. If it's an electronic egr valve then it's pretty easy to decide where to go from here with it. Even a traditional vaccum operated egr is pretty straight forward to diagnose and repair