Was driving home the other day. Driving at normal speed with no problems. Got to the stop sign right before my house. Jeep was barely idling. Had to feather it to keep it from dying. Pulled into the garage.. gave it a look over. couldn't see anything obvious that was wrong. Adjusted the idle screw on the carb 3/4 of a turn or so, and its running fine now. What on earth could cause me to need this adjustment out of the blue?