I have an O2 out of a 97, it's a 4 wire, same as my 91. According to the parts people it's a different sensor. Has anyone ever tried to interchange them? Can I?
If I remeber correctly the 97 sensor has a round connector and you 91 has a square. Take a look and make sure they are the same connector. It should work if thewy are the same.
That shouldn't be a problem-- some of the universal fit ones require you to splice them in, why not just splice it? Both are 4 wire sensors. Someone has tried this before I'm sure! It's free what can it hurt to try?