Check for vacuum leaks where the hose slips on , or at the TB gasket, or the elbow gasket. It would run rough if those were leaking though. Maybe the TB has a rough spot in the throat or the T-plate. Rub your finger over the edge of the plate and feel the path of the plate as the plate opens and closes. Be very careful when manually moving the T- plate, so you don't damage the gears in side.