Gilly, I came across this problem / description. Any additional insight you can give to the quote below? What does this fan do? The site the author links to for pics no longer works... so a more detailed description would be helpful. Is the diagnosis correct?
thanks!

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From Sam Truong (Sam_Truong@adc.com):

Ok, here are the step by step (from Tom DeTemple) with some minor modification and the pictures:

1. The front of the fuse box has a cover with two tabs. Press down heavily on the cover and flip the tabs off. Remover the cover exposing the fuse board.
2. From the front of the car, you will see two screws at the front. Unscrew the back pair until they are loose using the correct Torx or a 7/64" Allen wrench.
3. From the side of the fender, you will see three more screws on top of the black plastic cover with the emissions tags on it. Unscrew these until they are loose.
4. The cover should now easily come off.
5. From the side, look down towards the rear of the box and you will see a black cylinder (motor) with a Bosch sticker on it. That's the fan motor attached to the squirrel cage assembly below it.
6. Access to the fan you need to make room by pushing all cables to a side (see pictures)
7. Push back two clips. You need to wiggle the motor out of the inlet/outlet air hoses (see pictures)
8. I vacuumed dirt from the motor and inlet/outlet air hoses using my shop-vac. I also lubricated the bearings (per Wolfgang)
9. I tested the motor prior to reinstall by turning your ignition to the last position prior to start your trunk ( I don't know the correct terminology for this position).

Pictures
http://homepage.mac.com/koolimacsam/PhotoAlbum6.html

Result:
The noise went away and I didn't have to spend $80 to $100 to replace the motor. This task took me about 20 minutes.

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