Looking at the post Cat O2 signal I would say your cats are not working.
Post Cat signal is following RPM and Pre Cat signal very closely. Not as it should be.
Post Cat signal will have some rises and falls with RPM and engine load but should be biased towards a flatish signal voltage in the .650-.750 mil volt range.
There are some good youtube videos on testing for exhaust restrictions.
Also if you look up ScannerDanner on youtube he has some very good videos on reading fuel trims and O2 signals to diagnose performance problems.
He is a professional and very good at what he does.
You can view his videos and have a visual of what your Post Cat O2 signal should look like (flatish) under different running conditions.
Perhaps some of his videos will give you some insight on your issues.
Last edited by blue62; 01-21-2021 at 09:58 AM.
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