I have a very noticeable whistling noise from inside the cabin towards the front of the car when it is cold outside. The noise starts when I'm reach about 20 mph and gets louder up to 40 mph. It goes away after I drive faster than 55mph. Also - when the temperature outside is over 45-50 degrees, the noise is not there. It is a very noticeable noise and even passengers in my car notice it. I've brought the car to the dealership twice and they keep telling me they can't hear the noise. Wondering if anyone of this forum experience this similar whistling noise issue. Thanks.

Kiet

 

Get someone else to drive it while you try to hunt down the source/location.

 

Sunroof open or closed when whistling evident?

 

Sunroof and windows are closed. I even turned off the heating to rule out the blower.

 

Turbo spooling up? Will the noise also occur when stopped and accelerator slightly depressed?

Not to be confused with the infamous alternator whine...

 

I don't think it's turbo spooling up since the noise is present even when my foot is off the gas pedal. Noise does not occur when outside temperature is over 40 or 45 degrees. But as soon as temperature drops, the noise is always there when car is coasting between 20 - 45 mph. It's gotta be the most annoying whistling noise. Even my 8 year old son can't stand it. Thanks.

 

Try turning the recirc on and off, could be the outside flap is stuck.

Also ice caught in places can cause noise.

 

Toureg -

Thanks for the suggestion. I tried that last night as well and it did not help any. turned on recirc and it did not effect it any.

 

When you turn off the fans, does it actually say Off on the display? I had lots of strange noises when my blower fan went. Only other thing I can think of is check behind the cabin filter, maybe a mouse got in and piled some junk in there.

Had a car once that had a whole nest behind the cabin filter, was pretty nasty and blocked a lot.

Also maybe a blocked cowl drain is allowing water to pool and freeze under the cowel an causes some wind dynamics that make the noise.

Can you let your car sit in a heated garage and it still does it? Not sure if you park outside or inside.

Do you have PASM?

 

The whistling noise is still there. What I do notice is when the weather is extremely cold, the noise is more pronounce. It also appear that the RECIR button has an effect on the noise as well. Although it does not eliminate the noise completed, it does mute it some when I switched to RECIR mode. The noise is also there when the HEAT is turned off. Not sure what to make of all this. Dealers have been no help and keep saying that they cannot reproduce the noise. Thanks.

Kiet

 

Try getting to a speed / condition where you can hear the noise well. Then crack open one window at a time to see if you can get a change in the noise level or pitch or anything. If not, then try the sunroof - cracking it slightly.

Can't promise anything but it may give you a solid clue.

 

I am thinking about what happens at those temperatures, lubricants change state, things contract, and water freezes. Which side of the firewall is the noise coming from?

Is the Porsche turbo a variable vain like my Ford Diesel 6.0? The computer will adjust turbo boost pressure depending on different environmental factors independent of throttle input.

 

Just an update on this noise issue. By chance - I figure out where the noise is coming from. When temperature is below 30 degrees, the noise is there when car is over 20 mph. The whistling noise is coming from directly above my head from the panoramic moonroof. If i push up on the moonroof to create more seal - the noise goes away. If I let go - the noise comes right back. From what I can tell - the seals look good. At least half the battle has been figured out. Now - it's still elimination time. I will update if I figure anything else out.

Kiet

 

the moonroof, its funny that you mention that.

When I first purchased my Cayenne, there was a problem with the moonroof as it would not close correctly. The Ford dealer promised to repair, but could not. I was able to have it repaired at the Porsche Dealer for just a few hours labor. The problem was not seals, but a simple track adjustment. Once Porsche took care f it, I noticed no binding, noise and it stopped leaking at the touchless car wash.

Before the Porsche dealer repaired it, I had the Cayenne at a different Porsche dealer. There is a mechanical crank to manually close the roof. Get the tool out an see if you can crank down on it to stop the noise. If it stops, you may just need some adjustments like be from the Porsche dealer.

 

Just got my car back from the P dealership. They said they recalibrated the moonroof and the noise is no longer there. I wasn't able to truly test this since the temperature was above 50 degrees when I picked up the car. The whistling noise is only noticeable when temperature dips below 35 degrees. I also have issue with water seepage at touchless car wash. I will see if that issue is resolved at my next car wash.