Hissing sound..

ksh8759 · 10-19-2010, 02:03 PM

Whenever I drive or start the cold engine (550i)

I hear mostly a hissing sound which bothers me a lot!.

I 've found that some vehicles do or don't

I've been to service center and they said it is normal thing and most of 5 series does.

Does any other owner of 550 has same experience?

jeffhoff · 10-19-2010, 03:22 PM

can you be more specific. Where is the noise coming from (dash, engine)? Does it only happen when the engine is cold? At high speeds? Low speeds?

I have a 550 and haven't noticed any hissing sounds, but I do get a lot of use out of the premium audio system as well.

ksh8759 · 10-19-2010, 11:42 PM

The noise is coming from engine, and it happens usually when the engine is hot enough
mostly at low speeds rpm between(1.5~2.5 at most). I can also ignore them by turn the music on very loudly, but I really hate that only my 550 does have this sound....

lindros2 · 10-20-2010, 09:29 AM

Fuel pump? Burning off / pushing out excess fumes/gasses due to emission regulations?

I think I read about this in Car & Driver (regarding the new plastic gas tanks). The challenge is pent-up gas/fumes is the #1 source of unnecessary emissions, and a pain for manufacturers to deal with.

jeffhoff · 10-21-2010, 08:26 AM

ksh - last night I specifically went listening for this and didn't hear it in my 550. All I hear is the fuel pump pressurize when I open the door and the AC fan spool up when I start the car.

One question, do you have the adaptive drive option? Could it be part of that system that helps change the pressure in the suspension and help level the car?

I do not have the adaptive drive on my 550, but on my previous X5 I could hear an air pump kick on to level the rear suspension.

10-19-2010, 02:03 PM	#1
ksh8759 Captain 55 Rep 752 Posts Drives: BMW 2013 E92 M3 coupe Join Date: Feb 2010 Location: 90220 iTrader: (7)	Hissing sound.. Whenever I drive or start the cold engine (550i) I hear mostly a hissing sound which bothers me a lot!. I 've found that some vehicles do or don't I've been to service center and they said it is normal thing and most of 5 series does. Does any other owner of 550 has same experience?
	Appreciate 0 Tweet Quote

10-19-2010, 03:22 PM	#2
jeffhoff Private 5 Rep 67 Posts Drives: 2017 Alpine White X5M Join Date: Sep 2010 Location: Texas iTrader: (0) Garage List 2017 BMW X5M [0.00]	can you be more specific. Where is the noise coming from (dash, engine)? Does it only happen when the engine is cold? At high speeds? Low speeds? I have a 550 and haven't noticed any hissing sounds, but I do get a lot of use out of the premium audio system as well.
	Appreciate 0 Quote

10-19-2010, 11:42 PM	#3
ksh8759 Captain 55 Rep 752 Posts Drives: BMW 2013 E92 M3 coupe Join Date: Feb 2010 Location: 90220 iTrader: (7)	The noise is coming from engine, and it happens usually when the engine is hot enough mostly at low speeds rpm between(1.5~2.5 at most). I can also ignore them by turn the music on very loudly, but I really hate that only my 550 does have this sound....
	Appreciate 0 Quote

10-20-2010, 09:29 AM	#4
lindros2 First Lieutenant 33 Rep 308 Posts Drives: 535i M-S Join Date: Mar 2008 Location: ... iTrader: (0)	Fuel pump? Burning off / pushing out excess fumes/gasses due to emission regulations? I think I read about this in Car & Driver (regarding the new plastic gas tanks). The challenge is pent-up gas/fumes is the #1 source of unnecessary emissions, and a pain for manufacturers to deal with.
	Appreciate 0 Quote

10-21-2010, 08:26 AM	#5
jeffhoff Private 5 Rep 67 Posts Drives: 2017 Alpine White X5M Join Date: Sep 2010 Location: Texas iTrader: (0) Garage List 2017 BMW X5M [0.00]	ksh - last night I specifically went listening for this and didn't hear it in my 550. All I hear is the fuel pump pressurize when I open the door and the AC fan spool up when I start the car. One question, do you have the adaptive drive option? Could it be part of that system that helps change the pressure in the suspension and help level the car? I do not have the adaptive drive on my 550, but on my previous X5 I could hear an air pump kick on to level the rear suspension.
	Appreciate 0 Quote