Well if it says O2 sensor, then your O2 sensor is bad. If you car is still under warranty, take it back. If not then youre gonna have to fork over some cash
if it is still under warranty take it to the dealer O2 sensors are not cheap, your looking at $95 for one. and the dealer will reset the CEL for you at no charge.
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Atlanta bolt on installer, UDPs, suspension installations@ $110, Y pipes, clutch installs etc..got a max need a supercharger installer bring it to me.