1991 Mazda MX5 won't start

I have plenty of spark! When I jump fuel pump up front with jumper wire you can hear pump running! I replaced ECU new fuel pump and new fuel pump relay! Still won't start plenty of spark! I cleaned all ground contacts that I can find still won't start! I also replaced MAS still won't start! I have replaced the four injectors! I check all fuses that are good! When I try to start without jumper wire no fuel pressure! When I jump fuel pump with jumper wire engine will run as long as I spray gas into throttle body! What am I missing!