Question

I have a code P0420 on my 1998 Honda Civic 1.8L, what could possibly be?

Answer 1

P0420 code is for a faulty catalytic converter. This normally has to be replaced to resolve the issue. Sometimes the rear O2 sensor behnd the converter can also be the cause. This needs to be tested with a scan tool to determine which part is the problem.

Answer 2

P0420 HONDA - Catalyst System Efficiency Below Threshold Bank 1

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