When I start my 2003 Audi A6 2.7T there is a deep "whrrrrrrr" sound and after awhile (when it is warm) it shuts off. But after so long that same noise comes back. Is this the cooling fan? Does it need to be replaced? Thoughts?

Thanks!

 

The 2.7T has secondary pumps for various things. Most make some noise when they operate. With the car cold, suggest you pop the hood, start the car, and then run out front and try to find out where the noise is coming from. At least pin it down to a section of the engine and maybe we can guess what it is. The radiator coolingfan is at the front, so that will be easy to eliminate.