Have the same problem on my 03 es300,but got curious about tranny fluid, and sure enough, the Lexus dealer had overfilled it about a pint, so I drained exactly a pint out from tranny plug and I can't believe the difference in po pick up and overall response...still has a bit of a lag but you can blame that on the BS drive by wire, but if you want a more responsive ES , make sure tranny fluid is exactly up to spec's I know it sounds strange,but seriously, with this car ....what have you got to lose ???