I have a 1983 with air conditioning and I can’t figure out where this is supposed to plug in at and what it even does. I am thinking that it is used for something with the A/C because on my other truck without a/c I don’t have this. Any help on what it does and also where the green plug connects to would be appreciated.

 

I "think" it's the AC fast idle control that is part vacuum & part electronic. I would ignorantly assume it plugs into a idle solenoid or onto the carb itself. But my 82 doesn't have ac so that's just a guess

 

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