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Re: <E36>Speedo Problems?

> I also tried this. On a long section of highway without trafic I set the
>cruse control to matain a constant speed. Then reset the average speed
>function on the computer. Stating the obvious, since the speed is constant 
>the average speed and instantaneous speed should be the same. Guess what,
>at a speedo indicated 80 mph the computer reads 76.
>
> Well thats two 328's, anybody else have a data point?
>

I asked about this exact same problem on this forum about two months ago.
The consensus was that this was not really a problem, so ignore it.  I have
an '83 528e.  I asked a tech at my local dealer and he said that the speedo
pickup is an electronic system.  Since the OBC is also an electronic system,
but the speedo is an analog system, the OBC is going to be the right number.
This, he said, is due to the irregularites in converting from a digital
signal to a linear scale.  This is also why, in my car, the error (indicated
vs. actual) increases with overall speed.

as always, YMMV
matt

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                                   ______ 	
Matt Pelphrey                    o/______\o     1983 528e
pelphrey@domain.elided           (oo=OO=oo)     Blue/Parchment
pelphrey@domain.elided       []------[]     133k
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