1997 Lexus LS400 Q&A

1997 Lexus LS400 Question: what could cause my catalytic to go bad

code PO431 PO420 PO430 -
Answer 1
old age or fuel issues. -
Answer 2
age and fuel issues. today's fuel uses more ethanol. residues cause clog's in fuel system's and exhaust system's. try fuel additive(specificly ethanol treatment). -