So I decided to run a wire straight off the 1-wire O2 sensor straight to a 3 inch tail I clipped from the O2 terminal on the ECU plug. The plug to the pin tested ok for continuity and so it means I'm on good wire between the sensor and the comp. I reset the codes and the computer via battery cable and fuses pulled for about 15 minutes. I just plugged everything up and ran it and instantly a code 21 has displayed. My code 52 knock sensor code isn't there right now because I have yet to rev the engine over 2K since reset. Over 2K and that'll hit too, but the code 21 is already displayed even with straight wiring from sensor to comp. So where could the fault lie now?

 

So rather than fix the problem, you hardwire a wire to the ECU?

Looks like to me the O2 sensor and wire was never the problem.

 

This has been too elusive for me Cougar, so yeah I cut right to the chase today.
Those were my thoughts too as far as the sensor and wire. This probably means there's something wrong with the ECU then? As far as it's brain is considered regarding the O2 sensor.
I just read too much that the ECU is the least likely part of the equation to have problems.