Listees!

I've seen references to using the O2 sensor present in some Wasserboxer
vans to adjust the fuel mix, or CO level, or whatever. As my '86 Digijet
Caravelle doesn't have one of those sensors, I'm thinking of using an
external one.

1:st question: Which kind should I use? I can easily get one-wire,
three-wire and four-wire sensors. I suppose the ones with three or four
wires have some kind of heating element in them.

2:nd question: Where should I put it?

3:rd question: How should I connect it, and how to interpret measurements?

Greetings

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    '62 Johan Nyberg, Sodertalje Sweden
    '86 Caravelle C    Necessary Pest
    '62 Kerstin        Wife
    '85 Aasa           Daughter
    '87 David          Son
    '88 Markus         Son
    '91 Jonas          Son
    '93 Tora           Daughter

    (Signature concept gratefully stolen from Tim Casey)
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