Fuel Pump whistle solution?

volvovera · Post by **volvovera** » 16 Feb 2011, 08:17

A few days ago I have posted a thread about the high pitch noise at the rear end. Now I track down the whistle coming from the fuel pump. Usually the noise starts whenever I start the engine. So this time I started the engine, the noise just stopped as soon as I pulled out the fuel pump fuse (fuse 33).
Now I am considering the causes to this high pitch whine.
1. whether a clogged fuel filter can cause a noisy fuel pump?
2. whether a fuel pressure regulator problem can cause fuel pump whining?
3. bad fuel pump?
May some one give me some suggestion?
Thanks a lot in advance!

my car is 04 s60 T5

RaymanSean · Post by **RaymanSean** » 16 Feb 2011, 09:28

Did the car continue to run? I am not the most familiar with the volvo fuel pump set up, but if the car continued to run then it sounds like you have two pumps, one low pressure pump located in the tank that primes the high pressure pump. The low pressure pump is usually a centrifugal pump and the high pressure pump is usually a sliding vane pump. None the less, the cause of the noise can be from failing bearings, worn commutator, or worn vanes.

volvovera · Post by **volvovera** » 16 Feb 2011, 11:24

Till now my car has run well and no apparent loss of performance.

RaymanSean · Post by **RaymanSean** » 18 Feb 2011, 06:48

I would get under the car while it is in the air and running and see if you can locate the source of the noise. It will not hurt or take much time to check the fuel pressure at the rail, so you might as well do it so you can cross it off your list.

volvovera · Post by **volvovera** » 18 Feb 2011, 08:15

Thank you RaymanSean!
Because currently I do not have the tool to measure the fuel pressure, can I use Multimeter to test fuel pump amperages?
Another question is that I do not know the normal amp for volvo s60.

Post by **jimmy57** » 18 Feb 2011, 09:31

Look at the driver's end of fuel rail on engine. Is there a grey fuel pressure sensor with three wire connector?
IF the fuel pressure sensor gets biased and reports too low fuel pressure then the pump will be run at a higher speed and a relief valve on fuel pump cover assy can squeal. The only way to diagnose this is with fuel pressure check.
If you do not have the fuel pressure sensor then disregard this as a possibility.