Code 176 & 177 after new O2 install

I dented my drivers side O2 sensor while re-installing my engine w/trans on the firewall & decide to replace it with a Bosch stock replacement. The passenger side has less the 10,000 so I left it in. I now throw the above codes & can't figure it out for the life of me. My A/F gauge is hooked up to the drivers side O2 & reads Stoich all the time (used to pan all around) Seems to be running in default mode, smells of gas etc. Any suggestions on what could be wrong?

I guess it's possible, but they ran the scanner twice. I think the O2 sends a rich signal, & the computer leans it out & vise versa. Thus throwing the codes. I just don't understand why, with a new O2 I would get these two codes.