Catalyst-damage-misfire at idle (MIL flashes immediately) (*2):
WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.
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(*1) The threshold value varies depending on the intake air amount and the engine RPM.
(*2) MIL flashing is stopped when the misfire counts are less the 72 per 170 revolutions