Heat margarine in small skillet. saute onion and celery over medium-high heat on grill or stovetop until onion is transparent. Cool slightly and add sage and pecans. Combine onion mixture with ground turkey and mix well. Shape into six burgers and chill well. Brush burgers lightly with olive oil and grill over medium-low heat 8 to 10 minutes, turning once. Serve burger with salsa on soft roll or bun.