2010- Idling/Hesitation and buck.

Hey guys, new to the forum and hoping to get some help. I just bought my first Mustang roughly a month ago and hate to say it has been nonstop problems. Problem started as an idle surge when in park.. never seemed to mind idling in drive. RPMs would sit at about 650 then suddenly drop, a click would be heard under the driver side, and RPMs would shoot back up to proper range, then another click. So far have put new plugs, wires, air filter, all 4 O2 sensors (NTK), an EGR valve, and the screaming demon coil pack. Turns out someone was chasing the same ghost as I am. Bank 1 sensor 1 had already been replaced, swapped it anyway. MAF sensor looks to be brand new. Throttle body is clean and seafoam has been run through it once. The problem after all of this has evolved. Now the idle only occasionally acts up, but all low speeds there is a hesitation(like a carburetor running too lean) then a sudden buck almost like it is just receiving the fuel. This is also an automatic. Current codes are: P0401- EGR flow insufficient.
P0053 and P0059- Both upstream sensors showing resistance. P2195-Bank 1 upstream stuck lean and the kicker, P0455 EVAP system gross leak/no flow. This is a capless system and through this entire process this is the only code besides O2 sensors that has remained consistent. I do occasionally smell a fuel smell in the car with the top down. I also occasionally get "check fuel inlet" on the DIC. Any help would be appreciated, and i know this is a hell of a post, but im at the end of my wits here. Thanks.
 
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Hey guys, new to the forum and hoping to get some help. I just bought my first Mustang roughly a month ago and hate to say it has been nonstop problems. Problem started as an idle surge when in park.. never seemed to mind idling in drive. RPMs would sit at about 650 then suddenly drop, a click would be heard under the driver side, and RPMs would shoot back up to proper range, then another click. So far have put new plugs, wires, air filter, all 4 O2 sensors (NTK), an EGR valve, and the screaming demon coil pack. Turns out someone was chasing the same ghost as I am. Bank 1 sensor 1 had already been replaced, swapped it anyway. MAF sensor looks to be brand new. Throttle body is clean and seafoam has been run through it once. The problem after all of this has evolved. Now the idle only occasionally acts up, but all low speeds there is a hesitation(like a carburetor running too lean) then a sudden buck almost like it is just receiving the fuel. This is also an automatic. Current codes are: P0401- EGR flow insufficient.
P0053 and P0059- Both upstream sensors showing resistance. P2195-Bank 1 upstream stuck lean and the kicker, P0455 EVAP system gross leak/no flow. This is a capless system and through this entire process this is the only code besides O2 sensors that has remained consistent. I do occasionally smell a fuel smell in the car with the top down. I also occasionally get "check fuel inlet" on the DIC. Any help would be appreciated, and i know this is a hell of a post, but im at the end of my wits here. Thanks.
Did you ever figure out what the problem was, im having the same problems with my mustang it's also 2010