GMBulley@AOL.COM wrote

>Example: The O2 sensor is a critical part of VW's Fuel Management system. It
>"burns out" at about 60k. The replacement is simple (less than $100) and then
>all is well in the world. Where *some* folks run into trouble, is the O2
>advisory light comes on (a milage-counting light that tells you when you've
>gone 60k), they figure, "Hey, the van's still running, I can ignore that".
>Wrong. Should've bought a Nissan with that attitude. A bum O2 sensor can cause
>a VERY rich mixture, ruining the catalytic converter, and possibly burning
>valves, or causing other BIG problems.
>
        Please elaborate...How does a rich mixture burn valves?
        I'd be interested in a word picture of the process.

        How rich (stochiometrically speaking) is a "VERY" rich mixture?
        Seems like you're talking about RAW, unburned fuel left in the
        combustion chamber after the power stroke?

        BTW: the recommended change interval in my 1991 Vanagon maintenance
        booklet for the OXS is at 90Kmiles...as opposed to the 60K for other
        VW models.

      OLTECO                         Ari Ollikainen
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