I hear it at a very specific throttle position and it sounds like really fast rattling, but disappears completely after a tad more gas. I can replicate it anytime hot or cold. It vanishes with a slight press further, not because of engine noise. Same noise regardless of speed or temperature.
It is definitely coming from the right side of engine (seated in car).

Really odd...Anybody got any ideas?

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k