code P0420

Hi, my name is Devin. I am an auto repair expert with the Car Genius team here at RepairPal. So sorry to hear you're having trouble with your vehicle. The P0420 code indicates that the catalytic converter is not operating as efficiently as it should. Since you've replaced the O2 sensors and the valve cover, the issue likely lies within the catalytic converter. Over time, it can become clogged or damaged, which triggers the P0420 code. Since your Cruze still has great power, it could be a minor efficiency drop rather than a complete failure, but it's best to have the catalytic converter inspected. If the converter is in good shape, this could also be caused by exhaust leaks or faulty O2 sensor circuits. If you need more advice, have any other questions about your vehicle, or would like to get connected to a RepairPal Certified shop near you, we have you covered. Give us a call at 877-913-1554, and we will happily help you out!