What is causing the whining noise in the fuel-pump?

I have a 1997 Volvo whose fuel-pump is making a loud whining noise. My
mechanic checked and found the fuel-pressure normal. Any chance that a
10% Ethanol mix to the fuel may be causing the fuel-pump to be so
noisy? Is it possible that the fuel-pump may quit?

Thanks

 

Mine did that on my 740... it whined for about 2 weeks... then it went out
and left me on the roadway (only time in 150k miles..).. I'll bet yours
craters in 100 to 600 miles from now.
Not wishing you bad luck just been there before.
I hope yours lasts for a million miles!!!!
but thats not how I'm betting...
ps my car ran perfect with the whining fuel pump right up until it would not
move another foot.

 

I was in my local Volvo shop recently, and they have a scope-like tool
that they can monitor a fuel pump with. They can tell, by liiking at the
trace pattern if there is high draw, or low or high speed, or whatever
ane where in the poles of the motor these patterbs appear, and they can
tell you how likely it is that your pump will fail by looking at this
pattern.

I sat the tech check out the fuel pump on a Mercedes that was cutting
out intermittantly. The tech showed me some patterns on the internet for
this tool that showed what pumps with odd problems would show up like.

 

The pump in my 242 just died the other day, didn't make any funny noises or
anything, though the current draw was apparently excessive as the connector
to the relay was melted. The pump motor runs but it doesn't pump anything, I
guess the impeller broke or something.

 

on my 740s, when the one under the car whined, it meant the one in the gas
tank was dead or dying.

 

If the pump under the floor is whining open the filler cap and listen to see
if the in tank pump is operating, quite often this is the problem and it is
loading the underfloor pump hence the whining.

 

The in-tank pump is connected to the fuel pipe with a bellows hose
that usually fails. When the tank is less than about 1/2 full the
fuel gets foamy because of the split bellows. Ordinary fuel hose is a
good replacement. Check the filter sock while you are in there. The
in-tank pump is cheep. Fix it before you fail the expensive one.