Hi well if anyone can help me with this i will really be gratefull i have a 97 Audi A8 Q and when i turn it on in a matter of 2, 3 seconds something under the hood starting to make a strange noice. Now if a i keep my A/c to the lowest nd turn it on nd off rite away the noice goes away but if i make the temperature just a lil higher that dosent help eather then nd the noice is anoying. I pretty much narrowed it down to my blower motor but whats wrong with it i dont know. I anyone has any ideas please tell thatnx =)

 

This could be two different problems. Both of the will requre
access to the fresh air blower motor/fan.
Check this link:

http://www.audipages.com/Tech_Articl...anreplace.html

My fan was making a constant noise so I had to replace it.
This could be your first problem, fan needs replacement, or you could
try to lubricate it (not easy, I tried but failed, my fan was too worn)

Your second possible problem could be the installation. What mounting the
side-covers of the fan, installation is very tight and a very small misalignment
could cause this sound when you change the temperature the plastic stuff expands
slightly and causes the fan to hit the plastic side-covers. I had this problem when I
installed the new fan. You will have to take all the covers away to see the fan totally.
Then install each thing one by one and start the fan every time to check which component
that causes this interference. There are three possible parts:
The large fan cover or the two side-covers (one on each side).

Good luck!

/Christian 4.2Q-95 (Sweden)