Q: Code p0421, but new catalytic converter installed. Worried it's placed too far back in the system.

asked by on July 26, 2017

I had a new exhaust installed with no catalytic converters. I had an exhaust shop weld a new one in, placing the second o2 sensor after it. I have the wires extended but it still throws a code. I'm worried the converter is too far away from engine and the first sensor.

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