It is a 3-wire sensor that outputs a linear 0-5v analog signal, just like every other 3-wire pressure sensor. You change the Linear/Offset numbers to...
O2s will still give you an idea if it's rich or lean in OL, it just won't populate the trims. 'Whatever it needs to make it run good' is solid advice...
Cylinder and injector balance test if you have the tools. If not, compression and leak down test it. Unless you enjoy chasing your tail, that's what...