I am hearing a loud high pitched sound coming from the stillen plenum! It is easily heard after I turn engine off and turn the accessory on so the pump runs. It is not the pump as I can move my ear around the engine bay and it is DEFINITELY coming from the plenum...and yes the pump is running and making turbulance in the reservoir. I'm guessing its either the heat exchanger or the MAP sensor...I dont think there is much of anything else. Oh and when I turn off the accessory I hear a really loud click....like a relay turning off and then it is silence. I grabbed a video of the sound, I will try to post it.
I searched for high pitched noise on hear but only found cabin noise...definitely not that.
I not sure I know of any good mechanics around hear so I might see what the dealership is willing to do.
Here is a link to video...sorry it 80M but its very loud...flash is turned on after about 10 seconds.
https://drive.google.com/file/d/0B1x...w?usp=drivesdk
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