Just replace both front ones and be done with it. You can get borg warner brand off ebay. 2 of them are less $$$ than going to parts store for just one.
I had code for my drivers side one as well. Replaced it. Then day later got code for passengers side one. Ended up replacing both from sensors with the borgwarners from ebay. That was 6 monthes ago and no problems since. I also do not have cats and have the elimnators on the rear sensors.
This will fix you up. http://cgi.ebay.com/ebaymotors/96-9...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories