The vac lines to the PAS rack are quite useless anyway, well they have a small purpose but never mind that. Take the vacs off the rack and make a loop for the ports. And do the same with the lines up top next to the inlet, loop the ports so none go to the rack just to see if it goes away. Also is the inlet mani, or vac rail cracked at all, even the tiniest hairline crack can cause hunting. Vac leak causes hunting, not constant high idle