In a large dutch oven, saute onion and set aside. Brown sausage and drain.
Place sausage, onion, celery, carrots, tomato sauce, diced tomatoes, worcestershire sauce, garlic powder, sugar and 1 cup water in dutch oven. Simmer on low heat for 30 minutes.
Add pasta and 1 1/2 cups of water and cook until pasta is a la dente. (or you may add your leftover pasta and cook until just heated.) I have found that the sausage and tomatoes provide a large amount of salt. Therefore, you will need to do a taste test to see if you want any salt added.