I am a senior person and had very bad experience with Rockville Auto Clinic for repairing my car. When I drove my car to Rockville Auto Clinic, I told the service manager that recently my car randomly has error sign of Malfunction. He said that the problem is most likely caused by either the Timing Chain or by the Bracket, but he needs my permission to open the car. I gave him permission to do it. But when I picked up my car, I asked him if any problem is from the Timing Chain or Bracket, he said that he did not do it, but instead he replaced a valve and then asked me to pay $687 for the work. I asked him why he did the work without my permission and my knowledge because the car is my property. He refused to answer my question and said that he fixed the problem and forced me to pay $687. Even worse, after the repairing work, my car can only be driven about 15 minutes to home and then totally does not work at all. On the first business day of this week, I called the service manager. His assistant asked what my name is and then told me the manager will call me back. But he did not call me. I had called him 5 times from morning to afternoon, he refused to picked up my calls. The $687 is big money for a senior person. I have to find another auto shop to repair my car and spend more money.