My kia runs great then cuts off during driving, It starts up with no problem and may run with no prblem for some time. I have replaced the fuel pump and filter, had it diagnostic, the only code that shows is the oxygen sensor. It also have had the jiffy lube fuel system cleaning. any clues to what may be happening, the vehicle has 150k miles.
If it starts up right away, I would check out the ignition switch. You might be able to wiggle the key and see if the engine turns off.