I have not replaced the harness. I've made my way to the point of wiring in a temporary 1 ohm resistor to tell the ECU everything is fine. If that still does not solve the problem, I'll have to say it's the harness or the ECU. I'm doubting it's harness because it has only been in the car for a few thousand miles. But I'll have to check both ends of the knock sensor harness, like you said, before I can blame it on the ECU. I'll have to find some way of sending power through the harness to pick it up on the other end. Thanks!