The only comment I have is that some 4 cylinder models (actually many Camry) had the problem too so you are not immune. List:
? Camry 4 cylinder from 1997-2001,
? Camry 6 cylinder from 1997-2002,
? Camry Solara 4 cylinder from 1999-2001,
? Camry Solara 6 cylinder 1999-2002,
? Sienna 6 cylinder from 1998-2002,
? Avalon 6 cylinder from 1997-2002,
? Celica 4 cylinder from 1997-1999,
? Highlander 6 cylinder from 2001-2002,
? Lexus ES 300 from 1997-2002 and
? Lexus RX 300 from 1999-2002.