I hope I can call on your wisdom and experience.
I have an '01/CLS. Auto, 87K. For a while now I have been hearing a very strange noise.
The noise is similar in sound to the noise you make by taking a deep breath and then forcefully blowing it out as loud as you could. Of course its louder than what you or I could do. It comes at different times, at different speeds---mostly around 35/40PMH---on surface streets.When it comes, there is no noticeable change in RPM or drive feel. I lift my foot off of the gas for a second or two and it goes away. I thought it might be wind noise from an open window...but it happens when the windows are open or closed. Any ideas? Thanks!!!!!!!!!

 

where is it coming from?

 

I can't really tell. Sounds like a gust of wind is hitting the underside of the front of the car. Maybe it's a belt of sometype that is slipping. But again, when it happens nothing changes in the drive feel or the visible operation of the car. Strange.

 

transmission? has your tranny been replaced before. Is the sound more of a howling when your tranny is shifting from 2nd to 3rd?

 

The trannny has not been replaced. Seems to be okay. I'll listen a bit more closely to see if there a noise at that point. Thanks.

 

Mine was making the same noise ( like a wind noise but the windos were up) i found out it was cumming from the molding around my front windsheild. Try looking at the molding and see if it comes up. Sometimes if you wash your car with a pressure warsher or go through a machine wash it will move it. That may be the problem.
OR
look at the cowl panel (where the molding around the windsheild meets the hood) wind can get up their and make the same noise.
hope this helps, good luck

 

I had the same problem after about 1 month of me buying my '01 PDG. I did my best to clean out my IAC valve with some spray cleaner and did a transmission flush at the dealer. My transmission was replaced at around 60k miles and it now has 140k and outside of the tach jumping slightly when I am in 5th and going under 60 its done pretty well. The 'whoosh' sound as I refer to it had gone away until recently but its much less frequent. I will probably do another round of cleaning of the IAC valve and hopefully that will fix everything for another 6 months.

 

Thanks for the feedback. I'll look at the molding and look into the IAC valve stuff. "Whoosh" is a good description of the sound.

 

get your transmission looked at.