S10/T10 P/U 2WD V6-4.3L VIN W (1997)
The catalyst monitor sensors operate the same as the fuel control sensors. Although the Bank 1 Sensor 2 and Bank 1 Sensor 3 sensors main
function is catalyst monitoring, they also play a limited role in fuel control. If a sensor output indicates a voltage either above or below the 450
millivolt bias voltage for an extended period of time, the VCM will make a slight adjustment to fuel trim to ensure that fuel delivery is correct for
catalyst monitoring.
