fuel injector problem

[hockeypimp5123]

when i turn my ignition on and the fuel pump primes, the fuel injectors start spraying gas for no reason. The injectors are pulsing when the key isnt even in the car and it causes my battery to die. Like i said though what could be causing the injectors to pulse when the key isnt in the car and its just sitting thier. Somthing is sending it a signal telling it to spray i want to know what all could be causing it. Im not a nissan guy im just trying to help my friend out. so any info will help