fellas - i have an 83 cutlass cruiser with a 92 350 TBI from a roadmaster. if i drive at anything over about 30-35mph, when i come to a stop the engine continues at a high idle (1200-1300) for 30 or 40 seconds after i stop before settling down to 750rpm. i've checked the gas cable and don't feel it hanging up. any idea what might be the culprit? this is my first TBI car, i don't know where or what to look for.