Intermittent problem with starting and extreme gas fumes

Have had this since it was at about 160K. Check engine light always on. Temporarily fixed when dealt with a clogged egr valve. Has always had extremely strong gas fumes, especially in hot weather. Occasionally have issues in hot weather with slow/no acceleration then when it jumps forward and rpms drop, slow acceleration again. Now having issue of it not starting off and on. Leaning towards an issue with a connection from the ecu to throttle body or a short in wires but unable to find a wiring diagram to identify exactly which wires to focus on. I was able to get codes. Hope these help point us in the right direction. there were 13 total: P0420, P0401, P1404, P0402, P1125, P1295, P1340, P0300, P0137, P0420P, P1404P, P0402P, P0300P.

Any help is appreciated.