M.C.
My friend's baby did the same thing about the crying and not breathing. She threw a fit and screamed, stopped breathing, and passed out. Her parents could not arouse her so they took her to the emergency room. He brain had a lack of oxygen. She was OK but scary for mom and dad nonetheless!
Hopefully it is a phase she will grow out of but when it gets to the point where her breathing becomes and issue, I would pull over and soothe her. Try little toys that light up and sing songs or one of those mirrors where she can see you.