See Pic. Is the part that the Arrow points the part that you replaced?
A nice Fix.

If so I think that is what is wrong with My Door Vacuum Actuators except that there is parts crimped on above them that keep you from changing the Rubber Sleeve (diaphragm).

I have not gotten around to checking the Trunk of the Fuel Door Actuator (Pictured)

Attached Thumbnails

 

__________________
84 300D, 82 Volvo 244Gl Diesel