Getting P0420 & P1283

Question

Hello, I have a 2005 Xterra that has both P0420 and P1283 codes. The P0420 says other codes should be fixed first. Does that indicate that the A/F (O2) sensor(s) need to be replaced as a first step?

Answer 1

P1283 A/F sensor 1

Yes the 02 or  A/F sensor should be done first, the purpose of the A/F or 02 is to keep the engine in fuel control, to  where the catalytic convertor can then manage to clean the emission emitted from the engine. When the A/F is non functional the fuel control is outside a emission rate where the catalytic convertor cannot clean the emission properly.

Comments

Hello Reynaldo,

I have sense replaced the O2 sensor on the driver side and am still receiving the same codes. What else could be causing this problem?

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Also, I cleared the self-learn info by unplugging the mass airflow sensor, running for a brief time, and then clearing the codes. Let me know if there is another procedure I need to do.

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For P0420 if you have a scan tool a good catalytic will be above .650 ml volts. iyou go below that you set a catalytic convertor code. and the convertor is faulty