Joined: Nov 2016
Oftentimes these get called a 'dashpot' but even though they look similar, they're not the same. A dashpot doesn't have any wires; it just eases the throttle plates closed when you snap them shut. It's intended to prevent stalling, sort of like those drawer closers in nice cabinets that keep them from slamming. Your solenoid is just what Redstang said. =)
I smile a lot. It makes people wonder what I'm up to...