Car running very different, 2caa 2ca6???

Ok, so Im new to turbo engines. Ive had the jb4 installed for awhile, however just got catless downpipes and fmic installed, and now im throwing the 2caa and 2ca6 code. I know those are for the 02 sensors at the downpipes. My car is not running very well, feels like theres no boost. I have dci's and i dont even here them going. I hear the turbo spool, and the my boost gauge shows pressure and then drop off within milliseconds. Can bad 02 sensors cause this? Much help appreciated!!