Code 0420 means i have to fix the catalytic converter or something else

Question

The code 0420 came up for my 08 dodge magnum and after a few minutes of driving the car started driving slow and jerking when my foot was on the break only twice it happened do I change the catalytic converter or o2 sensors first

Answer 1

Hi there

The most common issue is the converter itself, if it's a bad O2 sensor it will be the rear one. Make sure there aren't any exhaust leaks, also that the engine is tuned and in good condition. Sometimes you can clear the code and try filling up at a different location. I have seen the fuel additives cause the code to come on as well.