Diagnostic test, is this a catalytic converter issue?

It could be but we need to prove that by following this guide that will help with this:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

The fact that you don't have a cat efficiency code is a good thing but the failed monitor means it is either starting to fail or you just did a battery disconnect or cleared the adaptive memory.

Have you recently wiped any memory or performed a battery disconnect?

Let us know what you find with this test and we can go from there. Thanks

It's the car I went to look at and I didnt feel comfortable after getting results of diagnostic test. The guy told me he didn't erase anything neither disconnected battery thank you for your help.

Another car had code p0182. I have no luck.

Oh, I understand. I thought you owned it. I think that was a wise move to pass on it if you were looking to buy them. Clearly I would not buy any of them if the issue is not fixed or they give you a great price because of the issues.

Thanks for coming back and updating us. Please let us know if you have other questions on this.