P0430? What to do?

[blue62]

Staircasesurfer

Here are two youtube video's to watch

https://youtu.be/RAC0E6apXq0
https://youtu.be/vyVnhCIMDnw

One shows how an exhaust leak can be the cause of the code.
Also a proper diagnostic procedure to correct the issue.

The other video shows that it was a Cat issue also using a proper diagnostic procedure.

Look closely at the O2 signal graphs in both video's.

The video by ScannerDanner shows the pre and post cat O2 sensors paralleling each other in frequency and amplitude. This is what JFP is referring to in his post.
But the test has to be done under the proper conditions as ScannerDanner has done.

The other video shows the post cat O2 sensor signal rising and falling with the pre cat O2 signal but not with the same frequency and amplitude. The signal is more biased to the lean side.
This is a signal you could also get if the cat was not hot enough.
Here again the test has to be done under the proper conditions for the test to be meaningful.

Hope they give you some insight into fixing your PO430 issue.