2015 V60 T5. Getting code P2274, reduced gas mileage,. Located upstream sensor p/n, but not the downstream. HELP???

 

Your downstream sensor is not part of that code. Downstream just measures cat health and doesn't affect fuel trim. Sure your upstream O2 may be bad, but no guarantee that replacing it will fix your issue. The code is telling you that the upstream is reading too much oxygen in the exhaust gases, hinting at a possible leak someone whether it be intake or exhaust.

 

Dingus, thanks so much. That is very helpful info to base further troubleshooting with! Thanks again

Robert