Sounds like you have a good old case of vacuum leak-itis. It plagues these cars because they live older than the rubber hoses do. DO a search on vacuum leaks in this forum there is tons of info on it. My car done the same thing to me except a tee fitting had broke of the main vac line even the emergency stop didn't work. So against my better judgement i was told to cut my fuel line. (chokeing it out at the breather didnt' work either). Hope this helps ya out a little. Any problems send me a message i'd be glad to help.