AE86 Oxygen Sensor help...

[Ian.G]

Hi guys,

trying to understand a little more about my hachi.

When I installed my T3 test/decat pipe this is what I removed.



as I understand it this is a catalyst heat probe. I believe this is only used to turn on a light on the dashboard if the catalyst breaks down and starts to overheat.

I have an o2 sensor in one of the primaries in my exhaust manifold (excuse the poor picture - it was dark)



This sensor has a single wire running from it. If I follow the wire I find its plugged into ..... wait for it ..... nothing. :o

Can anyone suggest where this *should* be connected to on the loom ?

I assumed my Freedom ECU would still be using the o2 sensor for cruise/part throttle and then not use it when the computer sees full throttle/closed loop.

Anyone have any suggestions ?