The harness connected to the engine and the ecu has a few other connectors which are involved. There are in my 93 FD a set of "two" connectors next to the EC which are white in color and have about 12 circuits. These two can be connected incorrectly because they look much the same and the fitting is interchangeable. I have a factory manual and it does not show the layout. One way you can connect the harness so as the white connector almost form's a "loop" the other is clearly different looking. I don't remember which way it came off. If anyone can shed light on this please let me know.