Ok, I took everything apart and gave the fan a good cleaning. All I really had to do was blow all of the dust out of it.

I put it all back together and now it passes the toilet paper test!

I bet you could clean out the fan with a can of air, like the ones you use to clean keyboards. If you do that:
-Make sure the key is off so that the fan is not running.
-Put something like a needle or very small screw driver up into the fan to keep it from spinning. It will have to be long and thin to go the length of the sensor tube and down to the fan impeller.
-Once you do that, blow the begingles out of it without fear.

Man, I love this site.

Thanks,

-Jim

__________________
1995 S350D, Green with black leather interior.
Bought January 2008 w/ 233,xxx miles.
I did 22,000 miles during the first year of ownership.