Mine sounds like it's right in front of the firewall beneath the passenger side windshield wiper. I almost started banging my dash to try and restabilize it.
Then I wondered if it might be in the air intake on the top right side of the engine.
I went fishing around and have found plenty of possible components in the engine bay that could be vibrating. They include tacked on relays and hoses crossing one and other, and even the spring on the throttle body. I'm rapping on everything in sight trying to recreate that vibrating sound.
The fact that it goes away when warm makes me wonder what's loose when cold and tightens up when warm. Like where incompatible metals or clamps are tied together.
(Please don't say cam shafts, piston pins, or main bearings!)
Then I wondered if it might be in the air intake on the top right side of the engine.
I went fishing around and have found plenty of possible components in the engine bay that could be vibrating. They include tacked on relays and hoses crossing one and other, and even the spring on the throttle body. I'm rapping on everything in sight trying to recreate that vibrating sound.
The fact that it goes away when warm makes me wonder what's loose when cold and tightens up when warm. Like where incompatible metals or clamps are tied together.
(Please don't say cam shafts, piston pins, or main bearings!)