million dollar minute - what's it for?

[kartone]

 8)Found, on the passenger side of a 1980 GTV transaxle, between the speedometer pick-up and reverse light switch 

[105gta]

Being on the intermediate flange, where the selector detents are, I'd say it's a neutral switch, not sure what it would operate, maybe for foreign market starter lock out??

[AikenDrum105]

is it to do with that emissions solenoid between the carburettors on some 80's alfas...  Holds the throttles open a touch on deceleration between gear changes ?  (I think there's a switch on the clutch too - only works if clutch is down and you're between gears ?  )   

Or I could be parading my ignorance there   let's call it a wild stab in the dark.

[kartone]

Drum105, yep, that's the correct answer. In my 1980 GTV there is a clutch switch, an engine RPM sensor and a solenoid between the two carbs that increases the idle RPMs.
I'm currently checking the electricals to see if this circuit also comes into play with the AC.