> >         Unfortunately the problem with just this is that the lowest
> >"engine on"
> >voltage may be below the maximum "engine off" voltage when you
> consider all
> >conditions. For example, on a really cold day the "engine
> running" voltage
> >might be below the "engine off with fully charged battery" voltage. TTYL
> >
>
> I would find that surprising, but I'll grant that it's possible.
>
> Measure the current.  It will flow one way as an indicator of engine
> start-up, and the other way until the battery is re-charged from the
> effort...

        Hmm, now that's a good idea, only problem I can see if you'd have to build
your shunt such that it could pass the hundred or more amps needed during
starting, without suffering a large drop. TTYL

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