Billman250

Seems you have a loose bolt somewhere. check the black heat shield between to motor and the battery. all 4 bolts must be tight.

Also, on a stock header, check for cracks in the top silver head shield, right on top where you can see. Right next to the valve cover. I have seen this make a buzz like that. If you find cracks take it off anf run it again.

ronnuke

This is what was causing my buzzing noise much like your video..my stock header heat shield had cracked due to vibrations making the buzzing noise during deceleration off throttle. My new header heat sheild was fine for a while but it too now is cracked and the buzz came back. I have resorted to ripping off a section of the heat shield that was cracked so the buzzing is gone once again. HTH

rob-2

I had a nut or metal on metal noise between 6500 up. It turned out my hood dampers (after market oil pressure lifts to hold hood up) needed some grease.