In a large pot over medium-high heat, heat the oil. Add the carrots, celery, and onion, and cook for 5 to 7 minutes, stirring constantly. Add the diced chicken and cook, stirring, for another 5 minutes, or until the chicken is beginning to turn opaque. Stir in the broth, salt, pepper, thyme, and parsley. Bring the mixture to a boil, add the noodles, and cook on high, uncovered, for 13 to 15 minutes or until the noodles are cooked to your desired firmness. Reduce to low heat, and simmer for 5 more minutes to combine flavors.