Graham W wrote:
> pravinkpant@hotmail.com wrote:
> > Exactly, in other words, the tone was there whether the engine was
on
> > or off. This is why I am ruling out a fuel pump. I can't think of
any
> > other buzzers or beepers that the car has. The lead to the positive
> > battery terminal did look as if something aftermarket had been
> > installed (an alarm system perhaps?) so I'm going to further
> > investigate to see if I can find anything. I'm still baffled
though,
> > because the tone was way too faint to be an alarm, yet too loud to
be
> > a keys-in-ignition buzz.
>
> It was the fuel tank breathing in and the pressure (vacuum) relief
> thingy caused the sound. Hint - almost completely close the back
> of your throat and now breathe in with effort - you'll get a similar
> noise!
>

The problem with this explanation is that the tone occurs regardless of
the key being in or not - i.e. regardless of the fuel pump being on.
Also, the noise is too consistent (as in, it's a tone of a particular
pitch) - think "Meep meep" horn being held down, but not as loud as a
regular horn. Also, the regular horn itself is unrelated to this noise,
and functions properly. The tone started blowing again on the way to
work - currently the battery is disconnected.

Any ideas, folks?