'86 Astro Van 4.3l Model 220 Tb Rwd Choke Problem And What's This Box?

The throttle/idle speed is a little high when the engine is cold, but it seems to stay high the 10 miles I drive it to work and back home. I cannot kick off the choke ever. I saw that this model year the idle speed is controlled by the computer, but what controls the high speed idle? I just bought this van so I decided to pull the engine cover and I found this throttle cable just lying there. I cannot see where it would hook up, or even if it's supposed to be there. I followed the cable and it goes to this box that's next to the battery. This box obviously controls the position of this cable, it has a wiring harness and a vacuum hose that route back to the intake manifold (just in front of the TB). The box is held in place with a tie strap. What is this box and how does this cable with the adjusting chain hook to the throttle or carburator