Rep Power: 0

I just did my first swap putting in a b18b into a ek hatch. I am using the p75 ecu and just wired up the things I needed in the original harness. I just did the timing belt, spark plugs and wires and the distributor rotor and cap. I am having surging idle and I can’t seem to find what it is, i start the car and it goes from 1000 rpm to 1600 and keeps going until it’s warm and goes down to 800 to 1000 and when ever I am in gear and try moving the car will stall. I have bleed the coolant mutile times now, cleaned the IACV and adjusted the fast idle valve. There is no vacuum leaks, I’ve tired adjusting the idle screw and won’t change, changed the map sensor and nothing.

what would be the next steps to look into? Change the iacv?