What wires are on your previous carby?
G13BA have there’s wires. One is for idle up when the alternator is under load (for example when your headlights are on) the other is perhaps idle solenoid (not sure off the top of my head).
G13BA


Yours looks like some sort of mongrel or a similar carby off a different vehicle, they’ve tried to earth out that cap in the pic which aren’t on any stock Sierra carby that I’m aware of. Looks to me like an electric choke.
For reference G13A only have one wire and where you have that plastic cap (? Choke spring) both G13A and G13BA have a vacuum activated hoobajoob
G13A
