P1133 1998 Toyota Camry where would the air-fuel ratio sensor be

Question

Trying to locate the air-fuel ratio sensor switch

Answer 1

P1133 A/F sensor heater circuit malfunction

Even though this is a A/F it is referred to as a 02 sensor , the location for this is the upstream 02 sensor which is the one before the catalytic convertor

 The upstream 02 sensor is the sensor before the catalytic convertro