I've been trying to figure out a problem with a rough idle. It typically develops as the truck runs at idle to low speeds on the trail. The truck starts the day running great and as the day goes it begins running worse and worse. This last time I pulled the lid off the air cleaner and observed what to me seemed like too much fuel entering the primaries. From the area indicated below. I would call it a dribble. It was more that just dripping. Does it sound like too much fuel? If so what could be the cause?