As the title states it's an 89 si. I'm doing a b20 swap. The issue I'm having is that with the pr4 ECU( I'm staying OBD-0) the fuel pump won't prime. With the d series ECU that the car came with the fuel pump will prime. Neither were working at first until I got a new main relay which is installed now. I checked grounds and all of that. I'm using an obd0 Integra distributor with d16a6 obd0 injectors on the si wiring harness. Do I have to do anything weird with the Integra ECU? Would the car at least start with the d series ECU to see how everything runs?