First pic is for idle speed adjustment, there is not plug attached there. See:
http://forums.pelicanparts.com/porsche-911-technical-forum/738091-85-carrera-warm-idle-surge-02-sensor-2.html
Second and third pics look like the Oxygen sensor connector as pointed out. There’s a number of threads on this topic this but this one has some pics:
http://forums.pelicanparts.com/porsche-911-technical-forum/745655-86-oxygen-sensor-location.html
In the pics notice the three stacked connectors, these are the sensors top one (white) is for cylinder head temp and lower two are speed and TDI sensors. They all must be connected. The lower two are hopefully marked and should be connected to right sensors. Some other threads on this if you search.
