crazy speedometer and lack of power

My '92 740 Turbo wagon has a speedometer that has begun to jump from
zero to thirty while idling, and when driving it will drop to zero and
jump up to thirty and back.

The wagon has another ailment at the same time, when accelerating and
it feels the wagon should shift, it backs off, as if you got off the
gas, or a governor clicked in.

Whether or not these two things are related or give a clue to the
problems of each I don't know, but it they both are existing at the
same time.

Any ideas?

Have you removed the instrument cluster recently? I have seen that
behavior in my speedometer. If you remove the instrument cluster and
misconnect the wires (tachometer to speedometer), that will happen. In
my case, it also fried the speedometer. I can't speak to the shifting,
as I have a stick.

John

on 9/14/2008, docsavage supposed :
> My '92 740 Turbo wagon has a speedometer that has begun to jump from
> zero to thirty while idling, and when driving it will drop to zero and
> jump up to thirty and back.
>
> The wagon has another ailment at the same time, when accelerating and
> it feels the wagon should shift, it backs off, as if you got off the
> gas, or a governor clicked in.
>
> Whether or not these two things are related or give a clue to the
> problems of each I don't know, but it they both are existing at the
> same time.
>
> Any ideas?