XSeries-forum

Hi all,

wondering if someone can give me some pointers about a strange loud whirring noise my 2009 E70 X5 30d X-Drive has coming from the front - it is like a grating sound and seems to be intermittent and last from 2 to 30 seconds. Usually from a cold start but sometimes whilst driving and sometimes after the engine is switched off.

I've looked around and have seen some comments about the suspension/compressor but those examples seem to only be for a couple of seconds long, not the 20-30 that I get sometimes.

I've filmed it this week - in this example it is just after I've turned off the ignition and lasts 30 seconds.

Video here:
https://youtu.be/snEIQoy9Ojg


Any help will be very much appreciated!

Hi and welcome to the forum

I'm not the best at there are others with more knowledge ad it's hard to tell without car running and then being switched off

I would probably say it's not suspension if the sound is continuing when the car is stopped or its on before the car is moving especially if sound is from the front. If it was from the rear it may be worth checking the air suspension conpressor if running, located in bootwell by battery.

Not sure where you are located or how cold it is at the moment but on some of the diesels they have a webasto preheater (auxiliary heater) which is supposed to warm the cars engine up when cold and kicks in at low temperatures.

So i would do a quick vin check to see if fitted if so it could be that
http://www.bmwvin.com/

link to relaoem auxiliary heater below
http://www.realoem.com/bmw/enUS/showpar ... Id=64_1586

If your car is not fitted with that then logically it would have to be an item that is moving to create the sound.

As the engine is off and it's still making the sound I would check fans or the belts visually to see if anything moving, Don't whatever you do try and put your hand in on a radiator fan as it could take a finger off, just have a listen to see if coming from there.

The fan is supposed to run on after being used to ensure the car cools down properly, but is unlikely to be running when you first start the car.

If the noise is from there if you have a look on realoem site as there is not a lot to one, and not too sure but it could be the bearing is worn, wait for it to cool and stop moving, then make sure you disconnect power to it first and then check for play in bearing. Not sure how good access to it will be.

Hth helps a bit
Graeme

[quote="simtekify"]
Hi all,

wondering if someone can give me some pointers about a strange loud whirring noise my 2009 E70 X5 30d X-Drive has coming from the front - it is like a grating sound and seems to be intermittent and last from 2 to 30 seconds. Usually from a cold start but sometimes whilst driving and sometimes after the engine is switched off.

I've looked around and have seen some comments about the suspension/compressor but those examples seem to only be for a couple of seconds long, not the 20-30 that I get sometimes.

I've filmed it this week - in this example it is just after I've turned off the ignition and lasts 30 seconds.

Video here:
https://youtu.be/snEIQoy9Ojg


Any help will be very much appreciated!
[/quote] sounds like a fan blade catching to me, lift the bonnet and see if you can pinpoint the sound more.
If the noise continues after the engine has stopped, as well as before it starts that elimanes anything engine driven.
A lot of BMW's do a test run of the auxiliary fan for the AC on start up, and the fan will also be turning after the engine has stopped for a while, as also is the main fan as it's on a clutch/ free wheel.
Look through the radiator grill too. Is there a fan visible, check the noise level when that's running too.

Hi guys,

thank you so much for taking the time to read and reply with your thoughts on my post.
Before going away over Xmas I checked under the bonnet and couldn't see any sign of blades catching and was going to do the air con test next but when I got back in the car I was greeted with this noise on a far more regular basis in a half-hour period, then a message on the dash "Level Control System Failure" with suspension icon, and after stopping and looking from the side I could clearly see that the back had dropped. After restarting the engine it did raise up again and get me home, but something is definitely on its way out!



Photos attached showing the back wheel arch difference:





I contacted the guy I bought the car from and he told me the car came from auction and when he bought it the rear was on the ground and he replaced both air bags so it does point to the compressor (or a leak but that wouldn't explain the noise). I am going to see how tricky it is to access the compressor and decide if to pickup a used compressor for GBP £200 or try a seal rebuild kit:

http://www.ebay.co.uk/itm/BMW-X5-E70-Air-Suspension-Compressor-Original-AMK-REPAIR-KIT-/

I guess I won't know exactly which part is to blame until it is on the ramp but might just buy both anyway so that I can fit the replacement compressor and then try to repair the old one in my own time...

Definitely sounds like the compressor.  I had mine go a few years back and it sounded like that.
I bought a new one from ebay for less than £300 if I recall.


Sent from my SM-G900F using Tapatalk

Hi

Sorry to hear the ongoing troubles

The link to realoem shows the rear suspension air bags and pump. I'm not sure if there is more detail on the pump
http://www.realoem.com/bmw/enUS/showpar ... Id=33_1379

It may be worth also checking no for leaks around the pipe joints if the airbags have been replaced recentl, just in case pipe has been pinched or is old and the pipe has developed a leak.

Iirc possibly one way to check is to use washing up liquid on all the joints then have the air suspension pump running (ignition on, but not necessarily the engine, so as to be safe) this will show any bubbles if air is leaking, which there shouldn't be apart from where it has the vent.

Hth
Graeme

Thanks all,

it was the compressor. I picked another complete unit up from ebay and swapped them out (followed https://www.youtube.com/watch?v=pVzQr6qJpHk)

All working well now!

I've opened up the old compressor to see what was wrong and 2 of the bearigns have rusted and the filter failed which has let moisture in which caused the bearings to rust and expand/friction - noise!