one wire off can act like that. both sides of the coil fire at the same time, cross one up, and it can miss at idle, and drive fine.

look for a busted vac line, maybe you leaned on one and it snapped or came off. you can always spray carb cleaner around the vac lines, see if the idle jumps up, if it does you found the leak area.

oh, the pvc, make sure thats pushed into the o ring in side the sc.