Hello. Can anyone please offer some insight into a problem that I am having with my 2003 E500? Two things.. the first is that when I set the AC on Max, after roughly 15 minutes of cool air, the rear vent begins to blow hot.. and I mean really hot! The local dealership told me that my "linkage" was twisting, but replacement of the unit solved nothing. Manual adjustments offer no help.
The second thing is that when I first I first turn on the car and crank the air, there is a loud and significant revving sound that rises in intensity for roughly 30 seconds before subsiding. Is this normal?

 

I am having the same first issue. I have a 2004 e500. I don't want to take it to the dealer unless I have too. Any suggestions?

Please help!!

Thanks