If you can try it for cheap, I'd say what have you got to lose.

I have never heard of anyone who was able to successfully clean a cat.
You may have more luck detaching the cats and trying to soak them with something like acetone.
I personally don't think any of the cat clean products that go into either the gas tank or the air intake will really do any good, but I've never tried it.
I also don't like the idea of putting anything in my fuel tank that will attack seals or other non-metallic components.

Out of curiosity, does it burn a lot of oil? If so, a clean may be what the doctor ordered. If not, it's possible that the cats really are degraded.

 

Doesn't burn a drop of oil or use a drop of coolant.

 

Those codes always mean that the cat(s) need to be replaced. There is no way around it. Don't waste money on anything else, the cats are expensive enough as it is.

 

Unfortunately you're right. My mechanic camera'd them and they are bad. now I'll have to fork out $1100 plus labor for CARB cats. Fortunately, I've got almost two years until I have to smog again and the car runs fine.

 

If going to keep car long term check out where cat converters are made. Price probably going up in near future if manufactured off shore.