[T77911S]

when you hear the sound, remove the air cleaner, reach inside and lift up on the air plate, but the key needs to be on. do not leave the key on for long since it is dumping fuel into the motor. you should feel resistance. if there is play, or the plate moves before you feel resistance, the plunger is sticking. or you can just go raise the plate with the key on and the sound you hear will be the injectors, which is the sound i suspect you are hearing. if that is the sound, it is the plunger.
techron in the tank may help. it needs to be driven, sitting makes it worse. i would put two bottles in now, take a long drive and do it several more times.

fuel rail was ok, i thought that is what you meant. the whinning was the key, if you had said buzzing, then i would have thought FP. the whinning is almost a squealing sound too.