I was busy last night. I cleaned out the vacuum pump, and it seemed to be operating ok. so I tried testing the line...whenever I had the climate control hooked up to it, it would work for about 10 seconds right after you started the AC(i guess trying to open the flaps) then it would stop, and then it would come on for 3 or 4 seconds every 10 seconds....like if there was a leak in the system.

So then I thought it might be in the line, or on the other end. So I found out where the line comes out (under the hood, right in front of the passengers seat). The hose connects to a small black box that has a lot of other connections on it, which I believe are the controls for the other vents. When I went to test the connections, the green hose's nozzle broke off(I swear I barely touched it!). So now I have a new problem....or do I? Because after it broke off, I checked the connections, turned the AC on, and guess what? The middle vents didn't work at all!!!! The only thing that wasn't connected was this green hose....So, I think that there may have been a crack in the nozzle, and that's where the leak was. So, today, I have to go by the Mercedes dealer to get a new nozzle....anyone have a trick for fitting these things...I couldn't even get the piece that goes in the hose off because its practically welded on. I ended up cutting it right where it ends on the hose.

Now my middle vents don't work at all, but the vacuum pump is also not turning off and on....so I think that's where our trouble is....As always, I will keep you posted.

I also took the time to take the door panel off last night, and found the problem with the window. One of the white brackets is split...shouldn't be expensive, but I wonder how hard it will be to take the window off of the sliding mechanism?

All in all, despite the small headaches, my car has been less of a headache than the Audi, Volvo(740 turbo), and Honda Passport I have had in the past.

ITS FIXED!!!!(I KNOW, I CAN HARDLY BELIEVE IT MYSELF)
 

Its fixed guys...thanks...total cost for AC repair:

$1.98.....yep...under 2 bucks!!!!

I traced the line last night to where it went into the black box under the hood....and that green nozzle that broke off last night that is in my last post was the culprit...I got the nozzle today and replaced it in about 2 seconds...took my car out in 104 degree Texas weather, and the middle vents stayed on, and the cabin temp dropped to a comfortable 71 degrees....


Thanks to everyone...

The bracket for the window was 86.00 at the dealer, so needless to say, I said forget it...they only sell the entire assembly, and all i need is one little plastic bracket.