My 2010 CRV is throwing a P0420. I've read up on the possible causes, and the two most likely are O2 sensor or catalytic converter. The question is, how can I determine which to replace? I don't really want to replace one only to find out it's the other.

 

Very likely the cat. A failed or lazy sensor has a different code.

 

My 2003 CRV burns through Catalytic converters every year or so. I believe that affects the O2 sensor readings?
Is it normal for it to run so hot to burn out the CC guts? Wonder if there's too much something coming out the exhaust manifold?

 

That is not normal at all. You are bypassing too much fuel or oil and the cat is burning it.

 

That's what I thought. Thanks, Ryan. Gotta figure that one out. I'm guessing oil since it is using about a quart every 1500 miles or so. 145,000 miles on it. Rings?

 

I also have 2010
CRV throwing the same code. I have a CA Cat but I have no clue which one to replace. I did replace both O2 sensors hoping it was that but the engine light is still on.

 

I also have a 2010 Honda crv ex that I replace both 02 sensors and the catalytic converter and the light still come on after I drive it 20 miles

 

I hope the codes were reset