car just started idling bad.some times will die. CEL also come on at idle.. i pulled a code 31 which is the AFM stuff... but the wierd thing is if i open the hood while its idling it runs jsut fine.. then i shut the hood and it idles bad :s no clue whats goin on there... i do have the unmetered air screw backed out so i dont get fuel cut.. but thats been like that for awhile .. any ideas?