"Normal" O2 sensor

[Garfield Willis]

On Tue, 25 Jul 2000 10:13:26 -0700, rhuish at goldrush.com wrote:

>I guess this data might well be classified as 'Extraneous'. 
>
>Fact: Blown head gasket pumping copious amounts of anti freeze 
>and oil out the exhaust system.
>...
>I suspect the long trips which involve extended turbo use and 
>associated higher exhaust temps, 'clean?' the sensor. Just a 
>feeling not based on measurements. Oh yes, before I forget, the 
>sensor was tested recently and pronounced "well within spec", 
>whatever that means.

I dunno why "extraneous"?; a known on-the-spot counter-example IS data,
ya know. :)  Now if you'd said you blew a head gasket and your O2 sensor
died 5yrs later right after a visit to Aunt Minnie's, I might consider
THAT extraneous. :)  Or casting serious suspicion on Aunt Minnie's
chilly.

All we seem to get are rumors on this contamination issue, which was why
I was trolling for more "factual" inputs like the above (consider it an
unwanted experiment Mother Science forced you into, just for this
purpose/destiny :). I've "heard" (once again, just people writing what
they "think" they saw on a darkNcloudy night when the lightning cast a
shadow, ifyaknowadamean) that carbon contamination from losing a valve
seal or the like, and then having it repaired sorta fairly soon, had
left the O2 sensor either lazy or sleepy, only to come back to life
after some more driving after the repairs and oil source was removed. It
may be that the source of contamination from antifreeze is ALSO a
reversible contamination process. Who knows?

BUTTTTTTT.... [caution, Farkle SES light is lit]

You wanna hear the juiciest of ALL O2 contamination rumors; I mean this
has gotta be the MOTHER of all O2 contamination rumors, and especially
as you'll see how it could affect the important is$ue of contaminating
WB O2 sensors with leaded racing gas, AND why the huge spread of results
people have been seeing on lead contamination (or not) with leaded
racing gas on WBs.

OK, drum roll.......I've been told this by two different sources in
private (juicier by the minute, huh?), OK two different private RELIABLE
sources (heh heh, better huh?), AND actually the subject came up because
I (MOI, ME, yeah this dweeb) was having the same suspicions from what
we'd been seeing with EGOR on lead, and brought up the question. So I
was sorta sniffing around for "explanations" (ya know, intellectually,
nature abhors a vacuum too, in more ways than one :).

OK, OK, I won't leave you hangin any longer... There's this "theory"
that if you "condition" the sensor in an unleaded environment for a
goodly few hours, and get it coated up with whatever deposits ARE normal
for unleaded-gas exhaust system deposits (ya know, the ones we know
DON'T harm an O2 sensor, other than age it some), and THEN you expose
the sensor to leaded gas, somehow the normal deposits protect it or at
least considerably delay it's contamination from the subsequent lead
exposure. OR maybe there's a layer that's constantly being deposited and
spalled off, and if you start with a goodly thickness of more harmless
layer, and later slobber some lead on it nowNthen, it gets cleaned off
without permanent damage.

BUT woe be told if you start a brand new O2 sensor off with leaded gas
from the get-go and it get's directly in the pores and under the skin,
sotaspeak; it will be in O2-sensor heaven in short order. Remember, what
you've just read is a RUMOR, not science, OK? So PULLLEEZEE don't go
quoting me as "Garfield said...nah nah nah".

Hell, I dunno; this is darts ya know, not science. An idea you think of
when you're on the floor, lamenting, "I've fallen, and can't reach my
beer". Heh.

This would explain why we can't seem to kill one with lead, because ALL
our repertoire of O2 performers here ALL were run for considerable time
in unleaded testing first, before we got up the courage to expose the
two we put aside for said destructive testing, that we did consign to
eventual murder-by-lead. So far, no murder; not even a hint of
aging/degradation.

Unfortunately, nobody I know of has been paying that close attention to
the history of their sensors, to see if there's a forceful correlation;
it's just something that more than a few people have begun to suspect,
thinking back at how their sensors were used in the beginning, and which
ones got hit with the lead early vrs late in life.

See now I told you that was a juicy rumor. And ya know what, just wadaya
spose will be the almost immediate outcome of us diligently spreading
this rumor around as fact!? Huh?? YEP, you guessed it, vendors will
forthwith spring up, offering an O2 sensor Conditioning Service!!! You
bet. Heh.

OR we'll see people saying, "we can't guarantee our WB O2 sensors for
even one hour of exposure to leaded fuel, unless you buy them *directly*
from us, cuz we slather on some special salsa on them at the 'factory'
here, and then shake'mNbake'm till their properly conditioned."

Then there'll be ads all over the place on how "You can make money while
JUST driving your car around". All you have to do is install a few
hundred O2 sensor bungs along your exhaust pipes, and O2 sensor vendors
will PAY you to condition sensors for them! Yup, a regular cottage
industry will form; I can see it know.

Oooops, I forgot, it's way past my time to take my medication.

Garfarkle


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