Vehicle: '93 S-10 Blazer 4 x 4 4.3L

Recently I started my blazer and it started fine. Got out on the road then approx. 1/2 mile from home started runniing rough, thought I would not be able to turn around andget back home. So the next day I started it up and same thing. I pulled off the vacuum hose on the brake booster and it smoothed right out. Plugged it back to booster and same problem rough idle and now dying. As long as I have the vacuum hose disconnected from brake booster it runs fime(although a little above normal idle rpm) and when I plug back to booster or even just place my thumb over the vacuum hose it dies. I have already replaced the brake booster with no difference.

Any help or suggestion will be appreciated.

 

follow your vaccum lines your brake booster isnt the culprit

 

Maybe sticking EGR.