No cat and no engine light

[supton]

Weird. But my '99 Camry is the same way. One day, for fun, I plugged in Torq to see if I could watch the O2 sensors. MPG has always seemed lower than it ought to be, so why not check for lazy O2 sensors? Front works as expected, rear is ... sitting at 0V. Always. ? Go online, order new sensor, put in over the weekend. No CEL. No change to how the car ran, either. No idea how it was happy with that. As a box-stock I4 Camry I am dubious that someone in the long past hot-rodded it and tuned the ECU to ignore the secondary O2 sensor, but I suppose that is always possible!