I have a 84 380 SE. I finally got it running with the install of a new fuel distributor. Now, it has an erratic idle but, when I turn on the air and push one of the vent selection buttons the miss go completely away and it is as smooth as a new baby`s backside. When I switch the air off the rough idle comes back. Are these vent selection buttons electric and operates some kind of vacuum switch, module or port. Anybody got any ideas?