P0157 on Toyota Sienna
P0157 code on an otherwise well running 2011 Toyota Sienna w/ 76K; replaced rear O2 sensor and erased the code. after one week and a tank of gas the code has returned. I replace the original sensor w/ an aftermarket sensor form Autozone. Question: could the forward sensor be causing an issue w/ the post catalytic converter sensor? any insights? thanks for your attention.
Upstream sensor will not affect the downstream one. Get a downstream sensor from the Dealer...more $$$ but likely worth it.