O2 voltages

[Bruce Plecan]

These are my observations and first impressions, and as I distill things,
and get more time with the WB I'm sure they will be revisited, and expanded
upon.
One thing that I'm totally clear on now, is how useless the oem gm O2
sensors are, for anything other then their intended use (as being rich /
lean, switches).
I was able to run the WB on several cars, with several different monitors,
and watch the displays.
With all the filtering averaging etc that the ecm and scanners do, there is
time delay from when an event happens till when reported, and datalogging of
what the ecm is doing includes all the filtering.

What's this really mean?.
You still need to know tuning, and tune up.
When using the oem O2 for tuning, your quessing,    it will just
****reliably**** tell you something when there is a major problem, and maybe
the magnitude of problem, ie the oem sensor voltage dropped to .3v during an
event,   and the WB showed just slightly richer then room air!.  *****So*
what* looked* like* a* reported* leanness* (with the normal data logging and
scanner) was* actually* an* ignition* event*....

The actual output of the oem sensor is nothing like the output of the WB as
far as resolution of cylinder firings, as far as variance in cylinder to
cylinder.

I'd also wondered why GM went to watching crankshaft accleration rates
rather then synching the O2 to cylinder firings, well the above covers why
you can't do it.

Oem ones work excelent for what they are designed for.
WB's **can** be an excellent assist, to monitor trends in what you engine
like *relative* to performance evaluations,  and report back to you what the
engine ****LIKES****.
ie.  if it runs EXCELLENT (best), at 12.25 AFR, then you know, 10.75 is just
wasting gas.  Just getting back to doing what the engine *wants* rather then
you wanting it to run at xc.y:1 AFR cause that's what you think it needs.

The old saying of speed cost money has taken on a new meaning if you want to
solely rely on electronics to avoid having to learn much about tune-up.

Now, if ya think about the above, and how it applies to the world as we know
it many things get clearer.

Hope ya'll find this as interesting as I do.
I ya don't want to hear about it lemme know.
Bruce

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