Wideband O2


so what does a wideband O2 sensor do and how is it usefull for tuning your motor ?

. . Sorry for the dumb question, and yes i searched - cash
most hondas, with the exception of the 5-wire VX and HX, run a Narrow band o2 sensor, either heated (4-wire) or not heated (1 and 2 wire).

Most wideband meters have a 0-5 volt output proportional to air fuel ratio. Noarrow band units, like the stock o2, run close to 1 full volt for almost all ari fuel ratios that a car could possible run "well" under. That output is fed back into the gauge or tuning unit and can be converted into a precise air fuel ratio. The stock O2 sensor is very inaccurate for anything other than 14.7:1 airfuel ratio.

as you can see, lean or rich, its still throwing back just under 1 volt. it's near meaningless.
yup, cuz it has a meaningful voltage to return, 0-5 volts which directly corresponds with an a/f ratio (depends on the actual wideband. some may start at one and end at 4, and be less accurate for "steps" between)

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