So..you are just throwing parts at it? If it were mine I would check the mechanicals such as compression, valve timing and lash and sense there were issues with the tensioners check it. Then check the electrical such as system voltage, coil voltage, CPS/RPM sensor, grounds..kill switch.. ect. Then fuel supply as in volume and pressure, injector operation, IACV. If everything is in spec as per the service manual then I would try a different ECU.
If you don't have the equipment to do all this checking I strongly suggest taking it to someone that does cause these things can drive a man crazy even with having everything.