Is your signal wire a tiny bit thinner than the stock o2's wire. I'm installing a heated 4 wire o2 and just noticed that, and I'm concerned if the added resistance of the smaller wire will effect the signal or not. And if so then I need to exchange it for one with bigger wires.

Or if it's enough to worry about.

 

well ohm it out and see

 

I should've looked closer I guess. I cut the wire on the old o2, the wire itself looks about the same. The insulation is thinner.