let the weirdness continue
 

hi all...new sound emerged from the x....now when the hvac is on regardless if a/c is on or just the fan... when you accelerate you hear a faint constant noise and when you let up off the gas it goes away...if you shut off the hvac their is no noise..the noise sounds like whisling/ hissing noise..that is the best way i can describe it..it is such a weird noise that it is hard to explain..i almost certain that it is not an electrical noise..it only does it while moving because if i rev engine while parked it dosent do it...could it be a pulley or belt...any help...thanks rob

check the evaporator drain tubes. they end at the driveshaft and can transmit noise to the cabin right where the center air vents are. install these valves at the drain tubes to eliminate the noise 54 10 7 070 130 x2

^ ding ding. worked for me

hi killcrap...could you explain exactly where the valves are at drain tubes on driveshaft..i want to make sure i do the right thing...thnaks so much for your help...rob

From a search on the part number he posted on realoem.com, it is the item number 10 here:

RealOEM.com BMW E53 X5 3.0i SINGLE COMPONENTS FOR BODY-SIDE FRAME

the evap pipes are under car at rear of transmission , i think killcrap says to fit the valves onto evap pipes to cure the noise .

damn i have the same problem. i'll have to check it out

how hard is the install on this?

Here is a picture of this rubber piece at the end of drain pipes from moon roof (looking under the X5, right next to jack spot):

http://i263.photobucket.com/albums/i...2_1024x768.jpg

Wrong place, look for the drain tubes for the evaporator not the moonroof

these pics took 30 minutes to find , computer is working slow today ,
these are the evap pipes each side of transmission , taken whilst dismantling . hope it helps .