My sons '04 Sentra 1.8L had a variety of issues which we addressed:
1. Bad accelarator pedal sensor - replaced
2. Clogged cats - installed 2 new ones
3. Leaking radiator - replaced it
4. TB error code - replaced the TB and performed a relearn

After all the work he took the car for a drive and it did fine for about 20 miles. Then on the way home it started misfiring and gave a code for cylinder 4 misfire. We replaced the coil and now it smokes like crazy and the engine occasionally surges at idle. I no longer have the old (bad) coil to install to rule the new coil out, but it seems to me like more of a coincidence than a cause. The smoke doesn't smell like coolant, and I got 160-180psi across all 4 cylinders in a compression test. They also passed a leak-down test. I cant see that the coolant level is dropping significantly, and it doesn't seem to be burning any oil.

I'm about out of ideas.

https://youtube.com/shorts/ToSIdl5LFjQ?feature=share

Is your PCV Valve any good?

PCV tested good and I disconnected the TB coolant tube, just in case. No change. I did get a DTC over the weekend - P0300: Random misfire. Next step is to test the coils I guess since I have installed new plugs. 3 of my 4 coilpacks are new though, so not sure how I could be getting random failures as that indicates more than one is bad.

Still really fighting with this and need help, my next step honestly is to call the PnP and get it hauled off.

PCV is good, car smokes like a smoke machine, billowing clouds of it (see video link in the first post.) The idle surges up & down and is erratic. Coolant levels are unchanged, but the oil level is way down. I did a leak-down test with each piston TDC on the compression stroke and they all tested good. Car seems drastically underpowered at low RPM/speed.

There are only a small number of things that can cause oil consumption with clouds of smoke. Rings, Valve Guides, PCV Valve, PCV plumbing. Your compression test is actually low, standard is 192, minimum is 168, maximum difference between cylinders is 14. So 160~180 indicates issues on both counts. You should wet-test the low ones, if they come up then the rings are scrubbed-out. Bad valve guides can also cause clouds, but usually just on the first start of the day and gradually reducing to nothing as the engine warms. However, there will still be oil blowing past the bad guides, it just won't be as visible. Anything obstructed in the PCV system can cause lots of smoke, not just a bad valve. That includes kinked or mis-routed hoses and clogged baffles in the rocker cover.