Mix soy sauce, ketchup, hoisin sauce, white wine, honey and sugar in a bowl. Rub meat with this mixture and marinate for 3 hours.
Heat grill and place pork loin to cook. Brush meat with marinating mixture frequently, turning meat to brown evenly, until meat is done and juicy.
More pork recipes for the grill:
BBQ pork spareribs
Pork ribs with Hoisin glaze