Auto Air Conditioning & Heater Repair: 1977 mercedes air & heat, vacuum leak, vacuum lines
QuestionI have cold air coming out of the center vents hot air out of both side vents. like the heater is turned on. car is a 450sl conv. how can I fix this? the controls slide up an dwn, two on each side.
AnswerSounds like you have a stuck blend door actuator servo or vacuum leak under dash. As these cars get older the vacuum lines get brittle and the cables are prone to kinks. Do the slides work smoothly or do they give resistance at one or both ends?
