Infinity just shut off

Fuel filter and/or fuel pump. That would explain the lack of throttle response and why it will only run for a short time. I recently bought an '06 infiniti coupe 6mt and found some wiring issues and a couple of plugs not plugged in so check those too. Good luck and I hope I helped.

Try cleaning the mass air flow sensor ,that's the simplest cheapest possible remedy ,if that doesn't work try cleaning the throttle body position sensor D O NOT TOUCH the butterfly when cleaning .there are videos to show you how to do this .if you have made any changes partswise you may need to " have the car relearn" it's new parts ,just Google the part replaced alongside the word relearn for the Infiniti that you own.