89 240 wont inject feul, feul injectors changed and harness plugs cleaned?? help

[scottsi]

I have a 89 240, it was having problems running, misfiring, so i go over the ignition system and everything is working, so i mess with a feul injector wire and it starts messing up more, so i put new feul injectors in and it runs good, but when i mess with the last ( closest to the firewall) feul injector it starts doing the same old crap again, so i change that one as well, clean the plugs and attempt to start it, it runs for 15 seconds then dies, it has feul pressure, so i pull the rail out and crank the car and the feul injectors arent spurting out any feul, i cannot figure out why, please please help me