Check engine light is on and code P0420

2011 KIA RIO

160,000 MILES • 1.6L • 4 CYL • 2WD • AUTOMATIC

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The check engine light is on with code P0420.
I already checked the 02 sensor the upstream S1 reads .2 to .7.
The downstream reads 0 volts.
I replaced both sensors with new ones and still the same.
I don't have any leaks on pipes or manifold .
Car shakes a little but not much RPM are around 800.
Please help.
Thank you.

Jan 18, 2021 at 11:31 AM

SEVAG P

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hello

it sounds like catalytic converter must be replaced, its clogged or aged.

Here are a few tutorials to view about catalytic converters:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms

https://www.2carpros.com/articles/catalytic-converter-replacement

I've attached picture diagnostics steps below for your vehicle, and remove and reinstall the catalytic converter .hope it helps.

thank you.

Images (Click to enlarge)

Jan 18, 2021 at 1:18 PM