Intrepid '99 fuel pump noise?

Some time ago I was driving with my rear seats down and I heard a steady
tone that appears to be coming from the rear of the car. Now I hear
that tone in the background with the seats up. It's a constant pitch
regardless of engine/vehicle speed, and only fluctuates slightly if
there is a power surge, such as the power locks locking, so I feel it is
electrical in nature. The only thing that is back there that I can
think of is the fuel pump.

The pumps sounds normal when I turn the key to ON and it pressurizes the
fuel system for a brief moment. Also I can sometimes hear it going
through the leak detection sequence when starting it with the engine
cold, a normal sound since the car was new. My car has the California
emissions package since it was originally delivered in a state that
requires CA certification. For the '99 (and a few others) model year, a
leak detection pump was used; I think later years used another
technique.

Has anyone else heard the fuel pump make a steady noise? Is it a
problem?

Thanks!

Greg Houston wrote:
> Some time ago I was driving with my rear seats down and I heard a steady
> tone that appears to be coming from the rear of the car. Now I hear
> that tone in the background with the seats up. It's a constant pitch
> regardless of engine/vehicle speed, and only fluctuates slightly if
> there is a power surge, such as the power locks locking, so I feel it is
> electrical in nature. The only thing that is back there that I can
> think of is the fuel pump.
>
> The pumps sounds normal when I turn the key to ON and it pressurizes the
> fuel system for a brief moment. Also I can sometimes hear it going
> through the leak detection sequence when starting it with the engine
> cold, a normal sound since the car was new. My car has the California
> emissions package since it was originally delivered in a state that
> requires CA certification. For the '99 (and a few others) model year, a
> leak detection pump was used; I think later years used another
> technique.
>
> Has anyone else heard the fuel pump make a steady noise? Is it a
> problem?
>
> Thanks!
>

I can hear my '99 Concorde's (same car) fuel pump if I try, but only
standing in certain areas - a steady whirr - not loud by any standard,
and certainly not annoying. I've never analyzed the sounds as far as a
leak detection system sequence, so I wouldn't know about that. I guess
when it stops making noise is when we need to worry. 8^)

From reading LH car forums for a couple of years, it appears that fuel
pump problems on our cars will become very symptomatic (drivability
issues) before you notice any unusual noise characteristics.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')