Fuel pump on the way out?

[Ed Novak <Novaked@ix.netcom.com>]

Am I doomed?  My wife coasted home - tank bone dry - out of gas - on the
'93 90S (Tuesday morning).  I put in a 1/2 gallon (normally reserved for
the mower - ouch) and fired it up.  Took a few tries to to start, but
once it did I heard a "whooping" noise - kinda like a whooping crane or
jungle noise.  Straight to the gas station for a fill-up on Premium.
Still had the noise.  Let car sit for 8hrs (at the office).  Driving
home the car didn't make the noise.

I assume the noise is from the bearings from the fuel pump?  Any BTDT?
What am I in for if I need to replace this?  Any diagnostics - or will
it just die whenever?  It is rarely making the whooping noise now, but
does so every once in a while.

Ed Novak
'93 Audi 90S
'96 VW Passat GLX