i take the air cleaner off carb. when it idles it starts to stall. i cover the top of the carb slightly with my hand and it goes back to normal. if i take my hand away it will start stalling again. i have a carter afb 600 of a 302 v8. anybody know whats wrong? it also hesitates when i want to take off. it shakes as im driving off. please anyone with any idea i will appreciate. thanks.