Rattling sound at 2900 rpm

I'm noticing a rattling sounds only at 2900 rpm in 2nd, 3rd, and 4th gears. 4x4, 3.4, manual. Best way I can describe it is it sounds like a bolt is rattling loose in the engine bay (kind of like a higher pitch pinging sound). Only at 2900 rpm, goes away at 3krpm.

I was recently having a high idle problem but had it fixed after pinpointing it to the TB, so I had the TB re-bored. I would say that I only noticed this 2900 sound after fixing the high idle issue.

Thoughts???

 

Post video

 

I don't think the camera would pick it up, but I can try tomorrow.

 

Not sure if this helps, but I had a loose hose clamp on mine that sat on the back of the engine under all the vacuum lines. It rattled at a certain RPM and drove me nuts! Found it and tightened it.

 

I had same problem, it was a loose bolt for a plate above the header that holds up the intake. Yours might be different though.