[Diy_efi] Possible method of partial repair of damaged O2 sensor (was designed for O2)

[Mike]

At 05:07 AM 3/06/05, you wrote:
>I'm guessing that at least some of the Pb from leaded fuel probably becomes an oxide (PbO) in the exhaust stream that reacts with the ZrO2 of the sensor to form PbZrO3, a really stable compound that is not very volatile or affected by oxygen at high temperatures. If the exhaust is really reducing then it could be Pb or Pb2O that your oxygen rich torch cycle would convert to PbO and...

Wouldnt there be a probabilistic assesment of the nature of this reaction based on
the period of exposure in conjunction with the reaction energy, I mean would there
be enough heat for the period of time to make PbZr03 adhere strongly and make it
robust enough for permanent damage, what is the physical property of that compound ?

I did recall some small whitish flakes fly off when I turned up the heat, they
gave off a light purplish or violet hue in the flame but there werent many.

>Answer to your question: No.
>
>Or, a more socially acceptable answer: IMHO I doubt it.

Is the stable compound fragile, I wonder if the pre-treatment with a propane
torch and combination with vibration environment in normal use later
might be enough to provide some minimalist rejuvenation ?

Is the PbZr03 acting as a short or just occluding the sensor area, so a higher
impedance output results. ie. If a lower impedance output is expected
and the pre-amp designed accordingly and contamination occurs the output
will fall away. If a much higher impedance pre-amp were used instead would
the contamination be less likely to affect the output in that some area occlusion
could be tolerable ?

Rgds

mike




>Jay
>
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Regards from


Mike Massen
Perth, Western Australia
VL Commodore Fuse Rail that wont warp or melt !
http://niche.iinet.net.au