Stumble, unstable idle, no related codes

I have code for B2S2 voltage to high I don't think it is related as you know this sensor only monitor's cat efficiantcy however it acts like it is a vacuum leak stumble at idle and revs up intermittently to 1000 rpm I have a scan tool and have watched the fuel trims there is little change in short or long term fuel trim when this happens +/- 5 % the long term dose creep up over time to +14 % during idle Map is reading 30 or so Kpa that is about 8.8 in hg I think but comes down when accelerating or cruising (Like a vacuum leak) but I can not find a vacuum leak also it blows smoke it dose not do it predictably like ring or valve guides would but just at random I have replaced the PCV. And clues as to were to look next