How to make Honda HRA214 carb's throttle spring back to idle

OK, I give up. I removed and cleaned the carb, and after reinstalling it, the throttle plate does not rotate back to the idle position even when the throttle lever is at idle. It is basically at full throttle no matter what position the lever is in. I am almost certain it isn't the position of the throttle cable as the off switch works when the lever is pulled to STOP and the choke engages when the lever is pushed to FULL. I can't figure out what spring or other mechanism is supposed to make...

How to make Honda HRA214 carb's throttle spring back to idle