Question

My muffler has a small bang and is making noise, can this cause this code P0420 2005 Nissan Altima?

Answer 1

This will NOT cause the catalytic converter code. This code is actually caused by a lack of O2 in the exhaust stream from the converter. Most cases require converter replacement to resolve the issue.

Answer 2

P0420 NISSAN - Catalyst System Efficiency Below Threshold Bank 1

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