Interesting.... So when you say the STFTs are zeroed, that implies that they are a cumulative average over a period of time. At least to me, anyway. So they really aren't instantaneous? Just shorter duration than the LTFTs but still averaging over a set period of time? I guess when I get around to re-enabling my STFTs, I need to look at them more closely. But I do recall that their influence created a low amplitude sine wave out of the wideband's signal in earlier scans I did a while back.
I'm looking at the image and see that the two O2 sensors are not matched with the same peak voltage values. Would that be considered as being a problem? Is one sensor actually detecting a difference in the exhaust stream compared to the other, and that is reflected by it's voltage output? Or is it just variance in tolerances of the sensor itself with it being normal to have some sensors with a wider or narrower voltage range than others?
Also, I've read in several places that some people recommend setting the switching points of the O2 sensors to 450mv. If I remember correctly, there is a table in the PCM for switching points and different values are being used across the cells of that table. That table seems to imply that there are different demands trying to be met by altering the switching point rather than using a static single value. So what would I be sacrificing by ignoring the mutli-valued table and instead using a single static value?
With the above in mind, does changing the switching point of the O2 sensors, either higher or lower, have any beneficial results that could be considered and utilized?
Oh, and another thing. How many people will switch their wideband sensor to the opposite side to verify that there isn't a dramatic difference in the oxygen content of the "other" engine bank?
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