She's driving a fiat punto, I had one and it was a pile of poo....this could be one of any number of things....get it into a fiat dealer before it cuts out somewhere serious like the outside lane of the motoroway.
I had a Fiat Punto years ago. It kept doing the same to me . I'd be driving along then suddenly it would cut out for no apparent reason. I would sit patiently trying to start the blinking thing without any luck then suddenly it came to life and off I would go again. This happened a few times till I thought sod this I will have to take it to the garage. They had it on one of those electronic tuning machines for ages and said it was difficult to trace the fault. So they got some expert in. He put it down to a problem with the distributer so they changed it. It seemed to have cured the problem although I did part company with the car soon after. Hope this helps you and good luck.