Terrible idle stall at cold start

[Junkor]

I have a 1987 300zx, we have been working on it for over a year trying to get her running well. I have previously messaged about a year ago.
So starting the car RPMs shoot to 1200 falls to 850 then bounces between 100 to 500 with the occasional spike to 1100. Crack the throttle it drops hard then stalls.

Things we have done
Checked OHMS, voltage, continuity to every part or ground
Drained gas put clean
Vacuum leak tests
Fuel pressure tests
Replaced
Fuel pump/filter
Fuel injectors
Fuel pressure regulator/speed sensor
Air pressure valve cleaned connector replaced
TPS
CHTS
Plugs and wires
Checked ECU 3 codes all replaced and gone

We are at a loss we have done a few classics in the past but this one has started to drive me mad.

 

[MAPerformance_]

Try this:

Unplug your Mass Airflow Sensor while the engine is running. If the idle stabilizes to a steady but rough state and no longer stalls when you tap the gas you found your problem.

The fix is replacing the MAF sensor or repairing the harness pins inside that factory rubber connector boot because they love to back out and lose contact.

If that changes nothing your fix is inside the distributor. Pop the cap and check for oil leaking onto the optical Crank Angle Sensor disc or check the distributor shaft for physical play.
Give the MAF plug a pull first and see if she clears up.

Let me know if unplugging the MAF changes the idle.

 

[Junkor]

Ok thanks we will do that Tuesday. That was next on our docket. But needed to reach out. Not ignoring but will update Wednesday.