My 2015 Mustang V6 has the same problem, I've taken the car to three different dealerships trying to identify and fix the problem, the fuel pump has been replaced but the problem still exist, and at times, more than a dozen times I have no throttle control while driving on the highway. Now I'm driving the car with a computer (logger) installed and today the problem came back. I was able to logged the no throttle control (3 times) and no start. I told Ford I'm going to exercise my rights under the state's lemon law, hopefully my comments can help other Mustang owners.