Emily:

That hum/buzz could well be the electric fuel pump which is located under
the car behind the right front wheel and inboard.  With the engine
running hunker down beside the right front wheel and stick your
head under the car.  The buzzing probably will sound louder to you.  You
can stick your hand on the fuel pumb and feel the vibration.

On Fri, 12 Feb 1999, Emily Goodin wrote:

> [snip] but after that I started
> hearing a mid-pitched quiet hum/buzz from under the mid-cabin area.
> This lasted for the rest of the day of driving around town.  The next
> morning I started it, and I noticed the hum/buzz was gone, but the idle
> is now searching (500-1500rpm) and while driving, it occasionally
> "bucks" (right term? - hesitated/jerks, but it was very quick, not
> affecting the RPM indicator).
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Tom Young               young@sherlock.SIMS.Berkeley.EDU
Lafayette, CA  94549    '81 Vanagon
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