Once the CEL comes on, the car bucks like crazy at part or light throttle. It runs fine after I reset the ecu.
Autozone said there were 2 codes. One for the primary O2 sensor, the other for a fuel trim malfunction. Is the second one caused by the first?

Is the car running like total sh*t just because of the O2 sensor?(it runs fine when the CEL is off)

 

yes, the o2 sensor will cause the fuel code also....fix the o2....

 

but the o2 code will not hurt your performance. have the o2 checked before you drop 180 bucks for a new one

 

I was throwing that code for a bit. Then I started looking into why it was throwing that code. Turns out my flex part was falling apart and letting out alot of exhaust with no so much noise (controlled driving=quiet exhaust) and the O2 wasn't getting a good reading and it was robbing me of power. It was dumping too much fuel in and the car would get the plugs wet. Pull it out, check it first, check aswell everything else. You might aswell replace the O2 and give the car a cleaner feel. If you have a used one kicking around, switch it and try it out.