Alright was this a 4g15 equipped car originally, and does it have the 4g15 fuel pump still installed??
No BOV?? Really ... you need to fix that for sure. Turbo will surge when shifting and cause issues with the intake charge on decel. Simple part to find overseas (US or anywhere) and install into a pipe inline. Then you run a vacuum line from the BOV port up to your intake manifold port, likely one of the larger copper looking ones. Do you have functioning block off rubbers on the extra ports on the intake manifold right now?? If they crack with heat and time, they will leak for sure!
Okay, for stalling and high idle, there were lots of tips posted in your thread, from a while back. I just read over them again.
Have you got coolant hoses running to the throttle body and back to the heater core on the firewall?? Has the cooling system been bled of any excess air bubbles and do you get really good heat from the dash with the engine hot and the engine at idle??
Suspect parts - Idle Stop Switch on top of the TB, was it confirmed to make a ground contact and is the little plate in place from the screw on top of the TB to the nut/bolt that is one of the four that hold the TB in place? That metal plate gives a ground path back to the engine/firewall for the ISS. Very important to have that checked.
Next is the ISC, but you had that cleaned and likely it OHMed out okay with a multi-meter/DVOM (digital volt/ohm meter).
As Crackerman posted, you need to check the FIAV operation, it could leak internal to the TB which means pulling off the big plate on the bottom of the TB. There is a gasket that can crack in that area and leak vacuum and then boost when the turbo is spooling/spooled.
Here is a 91-94 DSM style o-ring for reference:
https://www.rtmracing.com/xcart/product ... 603&page=1
Do you have a Palm Pilot or small logger tool that can show you the data coming from the datalogger port on the car?? This is very helpful to see where the ECU thinks everything is set to. We can then determine where the TPS sensor is set (is it within the factory range for idle and does it see WOT wide open throttle when pedal is fully applied), and many other variables.
Timing - was this set with the firewall harness plug grounded, and the datalogger pin at the port inside the car, grounded also, AND the engine coolant near full operating temperature?? Does the car have a proper OEM thermostat installed ?
Once we know all of this, we can find out more.
P.S. What is the vacuum you get at idle, cold and hot.