What's the difference between regular cats and California approved cats?

[Logan21]

Hello I have a 2001 4.0L. I recently gutted my cats and installed antifoulers to try to trick the sensors. It threw codes for both post cat sensors. I am now looking to buy new cats but I am in a bit of a pickle. My tj had California approved cats. What is the difference between them and non California approved and can I run the non approved cats without throwing codes?

 

[Chris]

The California ones have CARB stamped on them, which is required to pass emissions in California.

 

[Logan21]

The California ones have CARB stamped on them, which is required to pass emissions in California.

So that’s it? They’re the same cats ones just stamped and the other isn’t?

 

[Chris]

So that’s it? They’re the same cats ones just stamped and the other isn’t?

That is my understanding, yes. There may be some differences internally, but externally they look the same minus the CARB stamps. I think the new ones will actually come with CARB paperwork as well to certify them.