Is this even used? I know the PFC uses the first O2 sensor located in the O2 housing, but what about the second? Can I just unplug it altogether?

Reason why I'm asking is I'm thinking of putting my wide band O2 sensor in there in place of the stock O2 sensor. I'm catless so that shouldn't be an issue. If anything it makes for easier wiring into the cabin.

Thoughts?

 

Not used. You can unplug it and use the port for a wideband if you have no cat.

 

thanks

 

assuming the second 02 sensor is used by the stock ecu?
Does it do an average between the two or something?

 

No, the second O2 does nothing except tell the stock ECU if the cat is functioning or not.

 

does the evo pfc have the function to turn on and off o2 feedback ?

 

yep under ETC, FUNCTION SELECT according to manual