Ac blowing problem on 1995 Mercedes-Benz C280

the air conditioning blowing does not work well, the mechanic mentioned that there is a vaccume manifold that regulates the flow of air to the cabin. now the air blows only through the sides, sometimes the blow speed increases and decreases automatically. plaese tell me the name of the manifold or what ever it is that regulates the blowing of air so that i may look for a new one. or how i can rectify this problem,

Hi, did you end up replacing the manifold? Or was something causing the problem?
yes replaced the manifold but no hope. when i hit the recycle button it works well but as it goes off, the blow of air reduces more than normal.
2 more answers , 4 more comments
I am having the same problem with a 97 C280. It is vaccuum leaks and the actuators of the flappers. Mercedes wants a lot (too much) to repair and replace. I just bought a manual to do it myself. Will post once I get it all changed out.
I am having the same problem let me know if you get it fixed thanks..

Have you managed to fix this yet ? as i have same problem
how much did they want to fix?

The air blows more when I am an the express way. Could it need another cabin air filter?
check to see what version software for your climate control. if i remember there is a TSB to upgrade version due to center vents not blowing. there is a procedure to do a diagnostic on the climate control, it will show current version. Google it. it could be vacuum leaks also. GL.