I believe my o2 sensor is starting to go bad. The co levels on the emissions readout are approaching the state limit. I noticed there are many sensors to choose from. They range in price from $30-130. I have a 86 na, what kind should I get?
I believe you can test the O2 sensor with a multimeter, but I agree that a Bosch has been stated to be a good replacement, both the one with OEM plug and one you'd have to splice in. I got an OEM plug one since I hate hacking/soldering into wiring when I'm not forced to.
CO emissions may also be catalytic converter related. That may be your next step.