engine stops while driving
on 1998 Volvo S70

starts and shuts off driving car and at stops dies

Asked by for the 1998 Volvo S70
You'll need to see what is shutting down, it will likely be the fuel system or ignition system.
I would guess it's the fuel pump, but a quick check of the fuel pressure and power to the fuel pump when it stops will reveal this, or if it's something else.
Diagnosis is needed first. Good Luck