Bank 1, Sensor 1 on 1998 Mitsubishi Eclipse

Does Sensor 1 mean the front sensor, or the one under the car?

Asked by for the 1998 Mitsubishi Eclipse
Sensor 1 refers to the O2 sensor in front of the catalytic converter. And bank 1 is not relevant, this only has one bank. (V6 and V8 engines have a bank 1 and 2, not 4 cylinder engines)
You're Welcome! What is the issue, is the check engine light on?