Quote:
Originally posted by lapuwali
Both are very temperature sensitive, and my guess on how the wide-band units work is they're a normal O2 sensor cell with a precision heater and temperature sensor operating in a feedback loop. If you know precisely both the temp and the O2 sensor voltage, you can know the mixture over a much broader range. If you deliberately vary the temperture, too, you can operate the sensor over a wide range of values.
As for needing one, just get ahold of Mueller and put in your share.
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They don't quite work that way. NB sensors are temperature sensitive outside the switch point, which occurs at the stoichiometric A/F ratio. The voltage output of an NB sensor varies with temperature with A/F ratios that are richer or leaner than stoichiometric , but the voltage output at stoichiometric is not very sensitive to temperature. The WB sensor has a NB sensor as well as a catalyst cell that can either consume oxygen if current is pumped through it in one direction or consume unburned hydrocarbons by supplying current in the other direction. A feedback circuit pumps current into the catalyst cell until the NB sensor reads stoichiometric. The polarity and the magnitude of the current signify the A/F ratio.
Andrew