your not alone.
couple thing can be done to help but it seams the route cause is worn out engine.
What I did was..
Make sure none of the hoses have cracks in them. this will make sure you have proper vacume.
Take off and clean any connections that might be blocked up with debris. (old oil, dirt, grim)
Pull valve cover and clean and pull baffels out and clean them as well.(baffles are held inside cover by 3-4 small screws.)
My thread that many helped on is here:
There were some ideas that were provided that I did not do that may help you.