Very high-pitched buzzing/ringing sound on passenger side

Hi everyone. I’ve had a high-pitched whistling/ringing sound under certain RPMs (1200-1800) from the passenger side for as long as I’ve had the truck. I replaced the wire gasket with the Sequoia one, thinking it was an intake sound. Ringing is still there. Took it to the dealer, they said it was the intake and that there was nothing they could do. My truck is all stock save a leveling kit. This sound is driving my crazy. I already have tinnitus, and this whistling/ringing is making it even worse on long drives. Does anyone have advice on what to do next? I love everything else about this truck, but unless I can get it resolved, I’m afraid I’ll have to sell it and get something else. Thanks.

 

Mine is more of a whiny sot of noise.......oh wait.... That's my little wifey.

 

Turn the stereo up..... that works on the wife too

 

temporarily, unlock the wire loom that goes to the ECU from its clip on the firewall in the engine compartment, it's towards the passenger side. See if that changes or reduces the noise.

 

I’m not that knowledgeable on fixing this stuff tbh. Could you point to some resources on how to do this? Thanks!

 

It’s the ECU rattling in the firewall. Get this fixed and wait for the next annoying rattle.