my check engine light came on and i took it to autozone and got a p0420 code. this indicates most likely a catalytic converter or something to do with the oxygen sensors. i had both oxygen sensors replaced and the light is still on. what do you think i should do before i shell out a lot of money to fix those problems. thanks. i was reading other peoples stories of how the light keeps coming back on even after these are replaced so i do not know if i trust the code for accuracy.