450SL difficult to start but narrowed down.

[Genbiltstein]

I have posted before and wrote about working on my '74 mercedes 450SL. the problem she has is.
Intake Air Temperture Sensor: when I unplug it the car starts up perfectly. I suspect it is because the injectors are putting more fuel during start up.
When I reconnect it she gets a bit on the stubborn side when starting and stumbles on acceleration until she warms up. Idles rougher.
When disconnected she starts up fine.

I can assume there is something going afault here. Am I bypassing the manifold pressure sensor when the Air Temp Sensor is disconnected? Is the Air Temp sensor unserviceable?
Is the dial at the bottom of the D Jet computer misadjusted from a previous owner? She runs like a scalded cat without the Intake Air temp sensor connected as it is.
GB