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O^2 sensor Voltage Means...?

948 Views 6 Replies 5 Participants Last post by  Eye8Pussies
I was wondering if anybody knows what the O2 sensor voltage equates to in general A/F ratios? as well, what are the ranges that an O2 sensor can read at all?

if 14.7:1 is about stoich, what would that equate about to in volts?

I'm asking because I don't have the money to spend on a wideband yet, so I was wondering if I could get a general idea with my autometer A/F narrowband, which has a range of....lean to rich. damn useless. I'm not even sure what the voltage range is on it.
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Haynes says .1V is lean, and .9V is rich, so maybe .5V, but it won't stay there. The sensor is pretty much calibrated to 14.7:1 and bounces below and above that, but I'm not sure what the magnitude of .4V swing in either direction corresponds to either. Crap, that probably wasn't helpful.
IMO you cant get any data useful to tuning aside from minor adjustments. My GP has a nifty powrtuner that came with the car that lets me monitor and log different readings like 02 millivolts, most GP tuners say shoot for 930mv at WOT for the supercharged cars but Ive seen several cars where 930 is way way too rich, or way too lean. You just don't know for sure... And with a roots blower on there its pretty dangerous if you go lean.
yeah, the problem with the narrowband is that it bounces around too much and isn't stable

that, and I have no idea what the range on the a/f narrowband gauge even is

*sigh* time to get a wideband

thanks guys
bouncing is what the stock o2 sensor is made to do, if you where to plug into the sensor outputs (which i have) they just bounce b/t rich and lean. if they dont, its a bad thing.
therefore a wide band is the way to go!
still not exactly what I'm lookin for...but thanks. Great info in there.

long story short, I need a wideband regardless. I don't think I'm running dangerously lean...or else I would have blown up my engine aready, but lean for sure.
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