91mercedes benz a/c
 

91 mercedes benz 350sd turbo air conditioning set on center vents comes on about two minuter the most ,and then directs all air to the windshield .was told the push button controler bad then was told a,c actuators leaking . we checked one by one with a vacuun gauge and heard all actuators working , need help very tough problem .ps and very expensive unit . 700dollars

Vacuum pulls the center vent open & the SAME vacuum line goes to & closes the defroster flap. LOSS of vacuum to those elements are a starting point!

those center vents are confusing. read your owners manual. sometimes they come on, sometimes not. they supply only outside air.