Loud Engine Noise problems of the 2019 Mercedes Benz C300

Tl the contact owns a 2019 mercedes-benz C300w. The contact purchased the vehicle on April 6, 2019. On April 10, 2019 he took the vehicle back to the dealer (mercedes-benz of sarasota, 4754 clark rd, sarasota, FL 34233, (941) 275-1293) because it shook violently while driving and the engine felt like it was losing power at 20 mph. Also, an abnormal noise was heard. The dealer stated that the failures were not abnormal. The dealer test drove the vehicle with the windows up and could not replicate the failures; however, they stated that the noise was due to a design fault that occurred when the rear windows were open. The contact spoke with the state attorney general's office and was advised to pursue his concern under the state lemon law. The contact called the manufacturer and was informed that the case would be assigned to a case manager and he would be called back within 24 hours. If the issue could not be resolved, the case would be turned over to an executive investigating squad. The dealer called the contact and asked for a call back. After several attempts to call the dealer, the contact had not heard back. The failure mileage was 1,700.