Preheat a grill to medium and brush the grates with vegetable oil. Thread the pork tenderloin, sausage, bacon, pickles, banana peppers and onions onto eight 10-inch skewers; season with salt and pepper.
Combine the mustard and olive oil in a small bowl; brush all over the kebabs. Grill the kebabs, turning occasionally, until marked and cooked through, about 12 minutes.