my xh is making a high pitch noise,when i turn the key to aux its there for a second but once the ute is running its constant, the noise is coming from behind the cab not the engine bay even when in neutral could it be the fuel pump?

I notice that nobody has responed to this post yet..
Yes, my XH has the same noise, but it is also not running well at all, will idle but die when I touch the acclerator pedal.
From what I have read on this forum and others, my problem could be that fuel pump or a bunch other things. Some of those things I have replaced, but still the same issue.