CA catalytic converter - 03 Toyota Sienna

Chk engine light is on. Checked it at Advance Auto and indicated either cat or the O2 sensor (rear). So, I went to replace the O2 sensor and learned the hard way that you can’t just unscrew the nut. I torqued off the stud to which the O2 sensor attaches. Muffler shop told me you need to heat up the stud/nut first to remove it. Oh well, lesson learned.

So, I’m looking at replacing the pipe with the catalytic converter attached since I can’t seem to fix the broken stud (or actually get the one I didn’t break off). The problem is, my car is apparently a CA model and has the special cat on it.

I live in VA. What sort of problems might I run into if I replaced the cat with a non-CA version? They are significantly less expensive.

This is for a 2003 Toyota Siienna

If you do decide to do this, (and I’m not recommending it), make sure the non-CA catalytic converter fits. I had the same question with a 99 Toyota Sienna. When I called the technical rep at Bosal, who is a large manufacturer of aftermarket cats, he told me the dimensions of the non-CA and CA cat pipes were slightly different and were definitely not interchangeable.