ML500 High pitched whistle??

[stella best]

HELP!! When i start my 2001 ML500 on a cold morning there is a anoyingly loud high pitched whistling noise that apperes to be coming from the passenger footwell area. The noise is present with or without the air con or heater fans on, with or without the radio, lights,wipers or any thing else that can be turned on or off. It sounds like an electrical rather than a mechanical noise (but what do i know) It dissaperes as suddenly as it started about half a mile down the road and is driving me nuts! My local MB garage have looked at it but obviously assigned the job to 'Mr Mutton' who failed to find any noise atall.
Anyone else heard this before??

 

[Blobcat]

Hi & Welcome,

I have only ever heard a high pitched noise form the pax side of my car when the AC was out of gas. The pollen filter is down on the pax side of quite a lot of MB's although I don't know about the ML's. I would check that the compressor is running on the AC.

 

[stella best]

Hi Blobcat
Thanks for the swift reply, i have had the noise for over a year now but it is only apparent on cold mornings a few degrees above zero and the air con has been fine all summer, however could it be connected that the inside of the windows steam up when first starting the car in wet/damp weather and it taking an age for the windows to clear.?
Cheers
SB

 

[Blobcat]

When was the pollen filter last changed?

 

[stella best]

As i suffer from Hayfever i should be able to tell you but,,,,,i aint got the foggiest! I ve had the car for two and a half years and its done 36K, had services done at MB Dealership as per book so unless its a standard service item then NO it has not been changed. If this could be some of the prob then is it something i could change myself? or would it be main dealer stuff?
Cheers
SB

 

[Mark A]

Hi, I had a similar problem and it turned out to be the ECU cooling fan. I took it out cleaned & sprayed it and it's been fine since. There is a new part, which isn't so prone to squealing. Have a look at this post.

http://forums.mercedesclub.org.uk/showthread.php?t=20206

 

[stella best]

Cheers Mark.A
That sounds just about spot on as to what my whistle is. Im going out to get drunk now ( sorry, i mean im gonna celibrate the new year in with a few light ales).Will check it out in the morning with a hangover & let you know the out come.
Thanks again and HAPPY 2007