[ASE_Tek0312]

Id go with the battery/alternator like sierrap said. If it makes a clicking noise when you try to start it I would guess the alternator. and since all the problems happen when your driving I would guess the alternator is the problem. the battery is mostly used to start the car and the alternator generates the power after the car has started. but it could be the battery if you turn the key when it wont start and there is no clicky sound.