Oxygen Sensor (O2)
NOTE:
If oxygen sensor output voltage is measures, a high impedance digital volt meter must be used. Use of a meter with low impedance rating can cause inaccurate readings and/or damage to the sensor unit.
There are two O2 sensors used in the Allante'. The Oxygen sensors used in the PFI system are closed end Zirconia sensors placed in exhaust gas stream. These sensors produce a very weak voltage signal which varies with oxygen content of exhaust gasses. As oxygen content of exhaust gasses increases, a leaner mixture is indicated by low voltage output (as low as .1 volt). As oxygen content decreases, a richer mixture is indicates by higher voltage output (as high as .9 volts). The ECM corrects air/fuel ratio in response to changes in these voltage signals.