Engine Noise problems of the 2011 Hyundai Santa Fe

Took my car in to Hyundai dealership in concord, CA on approx. March 17th of this year for previous complaints of engine suddenly shutting off while driving. Was told at that time that no error codes were recorded by the car's computer and that Hyundai mechanics could not find any mechanical issues with the vehicle. They then talked to Hyundai engineers and decided that possibly the cars throttle bodies could be a problem and told me they would do a "good will" replacement of this auto part. Since that time, I have driven the car approximately 1k miles without incident, until this past Saturday may 18 2013. I was in stop and go traffic, going at speeds between 5-15 mph. I pushed the brake to do a gradual slow, then went to push the accelerator but there was no power. I looked down to see my dash lights were present, but no engine sound. I slowed the car to a complete stop, turned the ignition off, then turned it on and the engine started right up. Again, as previous, no error messages appeared on my dash. The car has been driven without incident so far 200 miles since this last incident. The dealership has asked me to bring the car in and allow them test drive the car for a day hoping that this intermittent problem will occur for them. It appears to be connected to hitting the brakes, slowing, then attempting to accelerate. All times this so far this has occurred while driving on an incline. The vehicle currently has 35, 500 miles.

Was negotiating a left sided curve on the downhill side of a steep, windy road in a remote area between oakland and moraga, CA when I suddenly lost steering power. I went to hit the brakes and found that my brakes also had no power. I pushed very hard on the brakes and managed to get the vehicle to stop. Had I been unable to stop, my car would've gone directly over a very steep hillside that borders a reservoir. As it was, the rear end of my car was jutted out halfway onto the roadway and only a few yards from a blind curve. This particular spot also has no cell phone coverage. After putting the car in park, I noted that my ignition was still in the "on" position and that all the appropriate dash lights were on, but the engine sound was absent and the tach read zero. I did not notice any error messages on my dash. I turned the car off, then turned the ignition back on. The car started right up with no hesitation. I heard no unusual engine noises or experienced any difficulties with driving the vehicle. I drove to the closest service station approx. 3-4 miles from the incident location. The mechanic did a quick check under the hood, found nothing unusual and suggested I go directly to the Hyundai dealership. I took my car to future Hyundai in concord, CA. They ran diagnostics the next day, then reported that they "could find nothing wrong with the car. " I expressed my fear of driving the vehicle based on very rational safety concerns and what I felt had been a close call on my life the day prior. I also told the service person that a quick look online lead me to find several stories similar to mine. I was told I would need to talk with the service manager the next day as he was not available. I then called Hyundai customer service and reported the entire history of this issue. I have been assigned case # 5622448.