About the video; the P0300- Random/Multiple Cylinder Misfire Detected appeared on OBD2 reader. Problem started after installing new, NGK spark plugs, ENA coil packs, Nissan valve covers, Z1 Silicone PCV Hose kit, and new optima battery.
I've also cleaned Throttle Body and MAF sensor with CRC solvents.
Notice in this video; soon as it dropped down to 1k RPM, I gave couple of throttle revs and let go of the gas pedal. Then engine dies on its own.
Sorry I haven't posted in this forum for nearly a decade, so much and vast thread to dig into. Suggestions at the moment please.

FYI: Engine/Powertrain modifications are: Tomei Expreme exaust system and y-pipe, RPM Long tube headers, SPEC Stage 3+ clutch/fly wheel, & Nismo CAI in which tuned by UpRev.

 

Update:
After last week's video upload; I check each of new spark plug's gap all six measured at 0.043 inches. Then I replaced with new Fel-Pro plenum & intake manifold gaskets from Auto Zone. Also re-torque all spark plugs, plenum & intake manifold bolts to 96in/lb upon assembly. Note: with the new optima battery cranking at 12.0v with no findings OBD2 error codes.

 

Did you by any chance manually move the throttle plate on the throttle body when you cleaned it? That can cause all sorts of issues with a DBW throttle body. I'm not aware if it causing a no start issue though.

 

Yes I did. Anyways, UPDATE - After installing remaining Z1 PCV hoses which is passenger side and driver side vacuum hose. Also re-torque all upper plenum bolts at 100in/bls. I don't know if this was the entire discrepancy of the crank-but-no-start issue, but I found one grounding wire that wasn't reconnected from the day I opened up the old valve covers. In this video; I let the engine run for almost half an hour with only my old P0507 returning from last year with no other sign of issues.