i have this code on my what can i do?? on 2001 Toyota Solara

okay so i been having this code for a while i change the cat the sensors and some other parts im spending a lot of money changing parts i went to 4 diffrent repair shops. and the said its the same code their dont know what else to do help

by in Bakersfield, CA on April 25, 2013
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2 answers 2 comments
ANSWER by , April 25, 2013
What code?
COMMENT by , April 25, 2013
p0420 that code
COMMENT by , April 25, 2013
Where did the replacement parts come from? Especially the cat.
ANSWER by , April 25, 2013
If the cat is not defective or one last test could be to confirm is no false/unmetered air within the exhaust system. Best bet to have a qualified service center perform a smoke leak test while vehicle exhaust system cold. Good luck.