lithiumus

In the final stages of the swap and running into electronic issues. The H23A is a JDM motor, the wire harness is OEM USDM and currently the ECU is my OEM USDM F23A1. It's throwing random misfire codes.

We've tried various JDM OBD II Type B ECUs with no success i.e. PCT, P75, and even the OEM JDM ECU that came with the engine PCN / PCF with no success.

I was told that the Idle Contol unit has 2 wires for JDM and 3 wires for USDM. But why does the USDM ECU work and none of the JDM ECU?

The shop suggesting going to OBD I and chipped a P30 ECU with Wire harness. I need to bring the car back to have the throttle body changed.

I wanted to ensure that this is the right route to take as I've heard that going to OBDI requires distributor changes, fuel injector changes, etc... or is that only required when using an OBD I wire harness?

Is a P30 the best ECU to use or should I look for a P72 to enable the IABs?

Thanks.