1995 S600 (sold)
Ever since I got this car, I noticed that the heat / AC air volume does not seem high enough out of the vents. I can hear the fan really moving when set to high, so I know the fan is good. When I switch to RECIRC, I feel and hear a substantial difference in air volume out of the vents. I decided to pull the passenger side under-dash apart to see what might be going on. I see that the flap inside the car under the passenger dash closes and opens when recirc is turned on and off. I also checked the function of the recirc flap vacuum actuator above the pollen filter. It works properly, I can see that the door moves when commanded. I'm confused. I have this feeling that there is a flap, door, or some other obstruction blocking air flow when pulling fresh air. Anybody have any ideas on this?