2008 Ford Focus 1.6L Catalyst Convertor low efficiency threshold bank 1, what to do?

Question

2008 Ford Focus 1.6L Catalyst Converter low-efficiency threshold bank 1, what to do? Engine check light on with engine code P0420

Answer 1

Hi there

The most common cause for this code is the catalytic converter itself. Sometimes though the rear O2 sensor can bring the code on. Also, check for any exhaust leaks before the converter, that will sometimes do it as well. Most often however, the converter is the cause of the code and will need to be replaced.

Answer 2

P0420 FORD Code - Catalyst System Efficiency Below Threshold Bank 1

Read more: https://www.autocodes.com/p0420_ford.html