[razor1049]

Hello i have a 94 s10 blazer 4.3 liter v6 (w) that hesitates after i have been sitting in a line..like a bank teller drive thru or long stoplight, it then it has black smoke coming out of the exhaust. it starts fine and runs good while its warming up but then after i do notice that it does idle a little bit rough and i have noticed that it does smoke black while i acclerate. i have had a computer on it but shows no codes. any suggestions would greatly be appreciated. gas consumption has become worse.