The previous owner of my 1970 S1 played around with the HVAC system in the car and has made a mess of it; I am keen to return it to the original configuration.
Both the Flap and Heater Control Modulators don’t seem to function correctly. I know many people recommend replacing them with various third party offerings but it would be my preference to keep the original components and make them work as best possible.
I have pulled the flap control modulator apart and the rubber diaphragm inside seems in reasonable condition but I am unable to get it the reduce the vacuum passed through and in turn, close the recirculation flap actuator.
Has anyone develop a method or have any tips for restoring the operation of these components?
Sincere appreciate any thoughts.