fuel pump or the main relay(it controls power to the pump)or rust in the tank a bad senser(iac,egr,map,ex...)would throw a code.still check fuel psi at full and half full so you dont condem a good fuel pump if it is canging its the fuel pump.i have seen rust in the tank do some weard things go a head and pull the pump and check for rust or a hole in the pick up. your car is strange.