During the warranty period, the car has been repaired for the same fault four times. What should I do if I know the reason and don't replace the new parts?

Make sure they change your 4s. In order to reduce expenses, this is a way to deal with people's problems or problems that cannot be solved. You can ask the headquarters for a new car. This is the rights and interests of consumers, and now they have been ruined by these 4s, just for a little bargain. Some people also want to take it. If negotiation fails, please ask the local authoritative TV station to intervene, explain the problem and expose it to them. It is impossible to delay the warranty period without taking measures. Forget about you and change it yourself. For example, one year Highlander or Camry forgot that Toyota's brakes were not good anyway, and the owner stopped at the entrance of 4 S regardless of 4 S. The red sign on the car was responsibility, and his manager didn't solve the problem, so he didn't want to sell the car.