I bought a 2008 Honda Civic with a blown engine. The previous owner hit something on the highway which destroyed the bottom of the radiator. They kept driving until the engine fried.
I have replaced the engine and the car runs great. After driving it I got a P0420 code for catalyst system deficiency below threshold. I tried a new secondary o2 sensor from my 2010 (which is in perfect running order) and the light came back. So it is looking like the catalytic converter is bad.
I wonder why the cat went bad? The engine didn't ingest oil and I assume it didn't ingest coolant into the cat. Seems odd it would go bad.
Is there anything else I should check before getting a new cat?
Thanks
I have replaced the engine and the car runs great. After driving it I got a P0420 code for catalyst system deficiency below threshold. I tried a new secondary o2 sensor from my 2010 (which is in perfect running order) and the light came back. So it is looking like the catalytic converter is bad.
I wonder why the cat went bad? The engine didn't ingest oil and I assume it didn't ingest coolant into the cat. Seems odd it would go bad.
Is there anything else I should check before getting a new cat?
Thanks