Hiya,
My 2005 Scion xA has had the Check Engine light come on a couple of times lately, and since I own a ScanGuage II, I checked the code number: P0138.
I looked it up and it is a "high voltage to the oxygen sensor"
OBD-II Trouble Code: P0138 Oxygen Sensor Circuit High Voltage (Bank1, Sensor2)
Does this affect my mileage? It seemed like it does... Do I need to replace the oxygen sensor? Or is there something else that can correct this? I have a zero deductible extended warranty...