I have had this car for around a month and a half. On two occasions now, while coasting, the car shifted down hard and clearly something went wrong. While stopped & idling, the entire interior of the car started to shake. When I accelerated, there was no power, and mpg while driving at 40mph dropped to around 8mpg. This also caused the check engine light to come on. At the next stop, I put the car in park, and restarted it. This solved the issue. However, the car is a month old and only has 1100 miles on it. Far too few to be having mechanical issues.