Q: I'm getting a po420 code is it possible it could be due to my rear catalytic converter even though there's no sensors after it? Or

asked by on July 15, 2017

I'm getting a po420 code is it possible it could be due to my rear catalytic converter even though there's no sensors after it? Or Is it most likely my front one off the manifold? I do have two 02 sensors on both sides of the first catalytic converter by the manifold but no sensors before or after the rear cat under the car before the resonator. Car was bought new and every thing is stock.

The sensor after the first catalyst is the one giving you code P0420 and should be replaced if the catalyst is good and you have no other codes in the system.

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