If the lift pump died you may have hurt the injector pump...the pump may have been feeding it low fuel pressure for a while before it let go and caused damage to the injector pump. Best fix, after changing the injector pump, is to move the lift pump off the engine and as close to the fuel tank as possible. Just like on a drag car, electric pumps work best when pushing fuel, not sucking fuel from 5-6 feet away. Bad design, IMO, from the factory - putting the lift pump on the motor and not by the tank.