I assume it cranks but does not start?
If you can be 100% sure it is the file pump not running that is causing the no start issue. You could rest it by temporarily running a wire jumpering the fuel pump directly to the battery with a switch.
Next time it happens flip the switch, if it starts you have isolated the symptom and can start working on a solution.
You could also bring some starter fluid and spray it in when it doesn't start.
Most FI cars have an inertial switch to kill the fuel pump in an accident. It might be failing
Another thought is anti theft system???
