US EPA Standard vs California catalyst

We know that California cats are always a few hundred dollars more than standard ones as they obtain higher amounts of precious metals compared to the standard ones.

Is there a difference in software within PCM between the two which may include tighter cut points for reduced emission or is it simply a hardware variation.

I want to hear your thoughts and experiences. Perhaps someone has put a standard cat on a California one by mistake

CurrentDraw wrote: Perhaps someone has put a standard cat on a California one by mistake

:lol: Betcha someone has!

I had a similar experience on a 2012 Ford Focus. It had California PCM programming, but the vehicle (and the catalyst) were Federal. :blink: No amount of new catalysts would have kept that one happy in the long term.

In that case, I think it was a combination of catalyst quality AND software. I think the Federal cat was doing it's job by Federal standards, but not Cali. If it were the other way, Cali cat and Federal programming, it probably never would have known the difference.

So it is a combination of cat and software. I was not too sure on this topic.
Thank you Tyler

CurrentDraw wrote: So it is a combination of cat and software. I was not too sure on this topic.
Thank you Tyler

I'm still not sure on this topic, to be honest. :lol: There's no emissions enforcement in my state, so I rarely deal with Cali vehicles or the problems created by having two emissions standards.