Q: The code I get for the O2 sensor reads Bank 2 is that the upper or lower sensor and where on the engine is that located? 2008 Kia Rondo

Hello - Bank 2 the cylinder group (or "Bank") that does NOT contain cylinder #1. (Conversely, Bank 1 is the group of cylinders or "bank" of the engine that contains cylinder #1) On your engine, Bank 2 would be the group of cylinders that is closest to the passenger compartment. Sensor 1 is between the engine and catalytic converter (before it). Sensor 2 is after/behind the catalytic converter in the exhaust system. For assistance, I recommend an oxygen sensor replacement service performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.