While stopped at a yield sign waiting for traffic to clear so I may proceed with my left turn, I stepped on the accelerator pedal to make my left turn; however, my car did not go because the engine had turned off due to the auto stop feature. Once the engine restarted, I was no longer clear about proceeding with my left turn and had to apply the brakes very hard immediately to stop my vehicle. The auto engine stop is a dangerous feature that should not automatically be applied when starting the car.