ADD water to a medium pot; boil over high heat.
HEAT a non-stick skillet to medium heat; add olive oil and sausage. Cook sausage thoroughly; remove from skillet, cool and slice.
ADD pepper and onion slices to skillet and cook approximately 5 minutes, stirring frequently and browning. (A bit more oil may be needed.)
ADJUST the heat to medium low. Add sliced sausage and marinara to the skillet and simmer for 3 minutes.
PREPARE fettuccine according to package directions and drain. Add cooked fettuccine to skillet and toss to coat.
