stevenf

He found the root cause is the "Driveshaft adjusting nut" on the front half of the driveshaft got lose.

See detail and picture here:

http://www.clublexus.com/forums/ls430/770272-what-would-happen-if-this-nut-loosened-2.html#post8911244

I think I have the exact same "tinkering when feathering throttle" problem, the noise sounds like coming from engine bay, not from rear end or underneath.

It happens every time when throttle is at the blink of opening and closing, not only when feathering the paddle, it also happens when cruise control is transiting between acceleration to coasting.

Ancdmd, have you found out what's the problem in the end?