Just wirered up SC400 using crown trans I modified speed sensors and mounts, I'm using the factory ECU and sensors on the motor & trans. Things were fine until I when to tidy up the wiring and relays ect. Now the reverse is surging and it has gone from a low idle to a fast idle Each Time it surges I can hear a click coming from the selector on the side of the trans, This happens with the selector plug is plugged in and unplugged?