2000 Chevrolet Blazer possible vacuum leak

I have had my blazer sitting for about 7 months without starting it, I recently have begun trying to get it road worthy again. When I finally got it to start again, it sound like it has a massive vacuum leak by the throttle body and idles very inconsistently. It was very low on fuel so I filled up the tank and added a stabilizer to try and combat against bad gas. I replace the base gasket on the throttle body. I also did a smoke test to see if it would pull it in but I wasn't able to locate anything and no improvements with the little mechanical improvements I have done. I was wondering if it could be the egr valve? Map sensor? or if you have any other things you may suspect? Thanks, Tim