Here's some background for context. (apologies for the wall of text, but I don't want to leave anything out)
2015 2.4l Sport Sedan 6mt - 132k miles.

• Suspected near-seized piston rings after oil consumption was steadily increasing. Compression test revealed sub-par readings. Soaked cylinders with seafoam, turning the crank to move the solution through. Got to a point where pistons/cylinders were holding the fluid. Vacuumed out as much fluid and carbon debris as possible. Compression test numbers were good. Started engine, obviously a rough start as it was burning up residual released carbon build-up and fluid. Test drive out the gate in limp mode. CEL. After looking back I realized I was cranking the engine opposite of running and the timing chain jumped teeth.
• After removing the valve cover the chain indeed jumped forward 2 teeth. I noticed that even with this offset, the timing marks on the exhaust sprocket & chain compared to the VTC actuator & chain were spread further apart. Chain stretch. Replaced all timing components, water pump, belt tensioner, valve cover, spark plugs and installed an oil catch can. Rough initial startup but it evening out fairly quickly.
• 1500 miles after that I get a CEL. Code: P0507. Idling at about 1100rpm.
  • Checked for vacuum leaks using propane, didn't notice any changes in idle.
  • Removed and inspected throttle body. Fair amount of carbon build up. Cleaned without moving disc. Reinstalled with new seal and the idle went up to 1300rpm. In addition, whenever letting off the throttle in neutral the throttle surges, bouncing up and down until eventually comes back to 1300rpm. When the car is fully warmed up, at idle it will bounce from 1900rpm to 1300rpm consistently.
  • Cleaned the MAF and replaced the MAP after seeing carbon build up near it's intake. Bled the coolant. Pulled out the PCV valve (replaced a few thousand miles prior) and shook it, no rattling. Cleaned it out with carb cleaner, released the check-valve and got it to rattle again. Still have the surging, and same behaviors as above.
  • Purchased a Foxwell NT510 Elite scan tool and reset the TP position. After turning on the car I was greeted with a high idle (car was already warmed up) then settled down to a hair above 1000rpm (still high). No severe engine surging. If I throttle to 3000rpm and release it comes right back down to idle, then up to 1200 briefly. So, I still have a problem, but it's in a far better state than before.
  • So it's not surging nearly as bad as it was after the throttle relearn. However, I notice three distinct patterns.
  • It will surge while in a state of motion in neutral.
  • Calm to a steady idle when stopped.
  • When fully warmed up, it'll surge from 1100rpm to 1300rpm consistently. Occasionally it may hang for a second at 1300rpm.
  • With a cold engine I went around vacuum fittings and hoses again, just in case I missed anything and still, no change in idle.
    
    Here's a video of it while warmed up and surging.

If anyone has any thoughts or suggestions, I am all ears! Thank you.

 

I would want to see the following data; short term fuel trims, throttle position, MAP, and MAF.

It could be as simple as a vacuum leak. Try spraying around with a can of brake cleaner and see if the RPM increases.

When it's all said and done.... how would you feel about tuning it? No Hondata/KTuner needed either.

 

 

Mine is doing the same thing. Did you find out the issue?
Thank Mike

 

The fact that your PVC valve plugged up again after replacement indicates your engine has severe carbon/sludge buildup. I had similar problems but not as bad as yours.

1. Perform a BG Engine flush and change oil
2. REPLACE PVC valve again.
3. Replace Throttle Body with Honda unit. Not that expensive. Be sure to reset TB relearn procedures after installing new unit.

It is apparent your engine maintenance was severely neglected. There are passages that are probably dealing with sludge buildup, etc. My problems with rough idle and random RPM increase were solved with new throttle body.