My E34 is haunted

[James Lofgren <lofgren@xxxxxxxxxxx>]

Last weekend I was reading the newspaper and I heard a noisy humming sound
coming from my garage.  I went to investigate, just in time to hear the
humming turn to a "clunk" and stop.  It had been coming from my 89 535i,
which I had not started for a couple of weeks (I drive it about every third
weekend for a hundred miles or so).  I turned the engine on and everythings
appears to be operating OK.  What's going on?

My son speculated that perhaps a faulty fan sensor thought the engine was
too hot and turned on the fan.

Is this a reasonable explanation?  Anyone else care to give their thoughts
on this?

TIA,

Jim Lofgren
lofgren@domain.elided 

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