EFI throttle body whine

[thumpar]

My throttle body has always had a high pitch whine coming from it at idle. When I first got it I thought it was just the nature of the EFI. I looked into it last year and thought it might be the high pressure fuel pump but that is not it and it is defiantly coming from the throttle body area. Now I am leaning toward small vacuum leak. It will change pitch from a higher to lower randomly. I have a short video so you can hear it. It's the only video I have. The gasket kit for these is NLA but looked up the GM equivalent and it looks like that would work. Anyone have thoughts?

https://youtu.be/_OPB0QOiO7Y

 

[achris]

That sounds more like a coil harmonic than a vacuum leak. The injectors have small coils of wire in them. The change of tone is the duty cycle being varied. You may need to replace the injectors, or at least have them serviced...

Chris...

 

[thumpar]

It does sound more “electronic” to me like when a computer power supply is failing and you can hear a high tone change with load. I was coming up short doing research and vacuum leak was closest I could find but it doesn’t have much of the whistle. I will see if there is a local place to take them too when I get the boat out of storage. Thanks Chris.