Boil macaroni and cook until al dente, about 7-8 minutes. Drain and rinse under cold water. Do not overcook pasta or it will not be able to hold up once the other ingredients are added.
While macaroni is cooking, stir together mayonnaise, vinegar, sugar, mustard, and salt until combined.
Stir together macaroni, mayonnaise mixture, celery, and bell pepper. Place in the refrigerator and chill for 1-2 hours before serving.