I started to say no, and then remembered that my wife had some work done on it last year. I found the receipt and they replaced the plugs and ignition coil boots last year. Mechanic's notes say that there were no codes but minor skipping at low RPMs. I think this explains it!
Here's what it looks like with a warm engine, on the highway with cruise control set.
Getting voltage drops on the Bank 1 Sensor 2 (post cat). View attachment 52929
The B1S2 drop is from the B1S1 drop. Not a cat or O2 issue I would think Almost looks like the way Hyundai does their cat efficiency test after every start at the proper time.
