Check engine light turned on and p0420 code returned

Hi,

The most common cause of something like this is raw fuel entering the converter. Have you experienced a misfire or poor fuel mileage? Also, an exhaust leak, faulty oxygen sensor, or wiring issue can cause the issue.

Are there any other codes that are present? Any exhaust leaks heard?

I also want you to know that the catalytic converter on this vehicle is covered by the manufacturer for 8 years or 80,000 miles. See pic 1. Pic 1 comes from section 10 page 38 of the owner's manual and warranty information handbook that should have come with the car.

Let me know if this helps or if you have other questions.

Take care and God Bless,

Joe

No misfires, fuel mileage seems to be the same. Was told by dealership there were no exhaust links and I haven't noticed anything. Supposedly dealership checked the wiring and sensors and said they were fine.

This being a 2013 its 8 years is up.

Hi,

LOL, no it still has a lot of life. The issue, in this case, really needs to be identified by the dealer simply because it is likely an emissions-related issue that is likely going to fall under warranty. I would have them replace the converter again and see if it takes care of it. If it doesn't, then I would recommend contacting a zone representative for Hyundai. There should be a list of contacts in your owner's manual. Explain what is happening, how low the mileage is, and the dealer can't fix it. In most cases, they will jump in and get it fixed for you. The vehicle has very low mileage.

Let me know.

Joe