Early/Late O2 Sensors

[Digitalwave]

I have a nearly new early model 325i 4-wire O2 sensor I'd like to use on a late model wiring harness. They have different connectors. I need to splice the connector anyways to extend it because of my long tube headers.

Are the O2 sensors the same besides the connector?

[nando]

if it's a 4 wire heated sensor, yes they should be the same.

two grounds, one signal, and one for heater power.

[Digitalwave]

There's a black, grey, and 2 white wires on each. Only visual difference is one has a screw-together connector, and one is snap together. I'd imagine the 2 whites are the grounds and can be interchanged?

[nando]

yeah I believe the whites are grounds. I don't recall which is power/signal. On the engine harness side, the yellow shielded wire is for the signal, if that helps you figure it out.