Combine catsup, chili sauce, olive oil, brown sugar, minced onion, Worcestershire sauce, mustard, black pepper and wine vinegar in a bowl. Set aside 1/2 cup sauce.
Prepare a lightly greased grill for chicken, Place chicken on grill.
Grill chicken, uncovered, 5 to 6 inches over medium hot coals for about 30 minutes or ti cooked through, turning and basting with sauce 3 to 4 times during grilling. Serve reserved 1/2 cup sauce as a condiment with grilled chicken.