Hissing sound from fuel pump...

[Rick L]

I didn’t receive any response to my fuel pump question so I’m posting the same question again. I heard from few people from this forum that the hissing sound is normal but the BMW service told me that it isn’t. New fuel pump doesn’t make any noise (no buzz, no hiss, nothing…). My old fuel pump used to make the buzz and hiss sound but not the new pump. New pump will make slight buzz for 2 seconds when you turn the ignition "ON" but no noise after that. I talk to BMW service and they said the hissing sound from the fuel pump is not normal and they shouldn’t make any buzzing/hissing sound. If you here buzzing/hissing, something is causing the fuel pump to hiss. In my case, it was the clogged strainer. The strainer is under the fuel pump and most people WOULDN’T change the strainer unless they change the fuel pump. All the crap from the gas tank will enter the strainer before the fuel filter so why not take a look at the strainer and clean it or replace it. I think it's a good idea to take a look at the strainer when you change your fuel filter and make sure it is clear from clog. I replaced the fuel pump, strainer, and fuel filter. Now my car doesn’t make the hissing sound anymore. Any comment(s) on hissing sound from the fuel pump??? Picture below shows the clog (sorry for the bad picture).

[Bill R.]

to argue your point but you may have noticed that frequently your local bmw service may tell you things that aren't always true exactly...such as dash clusters can't be repaired they must be replaced or brake rotors should be changed with every brake job or transmission fluid is lifetime....The point i am trying to make is that many of us who work on cars for a living have seen many fuel pumps that buzz or hiss last for 50k miles or more making this sound, sometimes its related to how the pump is mounted, sometimes its the brand of pump, just because they say its not normal doesn't mean its bad. and frequently you can have a buzzing pump and pull it out and the strainer is perfectly clean but the pump still buzzes.... Also as a side note, most pump manufacturers require you to change the strainer anyway with a new pump as a warranty requirement.

I didn’t receive any response to my fuel pump question so I’m posting the same question again. I heard from few people from this forum that the hissing sound is normal but the BMW service told me that it isn’t. New fuel pump doesn’t make any noise (no buzz, no hiss, nothing…). My old fuel pump used to make the buzz and hiss sound but not the new pump. New pump will make slight buzz for 2 seconds when you turn the ignition "ON" but no noise after that. I talk to BMW service and they said the hissing sound from the fuel pump is not normal and they shouldn’t make any buzzing/hissing sound. If you here buzzing/hissing, something is causing the fuel pump to hiss. In my case, it was the clogged strainer. The strainer is under the fuel pump and most people WOULDN’T change the strainer unless they change the fuel pump. All the crap from the gas tank will enter the strainer before the fuel filter so why not take a look at the strainer and clean it or replace it. I think it's a good idea to take a look at the strainer when you change your fuel filter and make sure it is clear from clog. I replaced the fuel pump, strainer, and fuel filter. Now my car doesn’t make the hissing sound anymore. Any comment(s) on hissing sound from the fuel pump??? Picture below shows the clog (sorry for the bad picture).

[winfred]

ditto, once it gets some wear on the impeller/rollers or whatever it uses some noise is going to be made, and sometimes new pumps are noisey till they break in. i've been having problems with the new bosch intank pumps working for a day or two then needing a bump to start back up, i think they are using a dirtyer brush or a different cut on the brush that fowls the comm, once you get some run time on them they are fine

have seen many fuel pumps that buzz or hiss last for 50k miles or more making this sound, sometimes its related to how the pump is mounted, sometimes its the brand of pump