[cotbu]

NID?
First thing to do is pull ecu codes, I don't wanna hear tings like the check engine light isn't on. just pull codes first, make it a habit.
93oct is harder to detonate than ether, aka use ether instead. just temporarily.
How could you come to the conclusion the air, in the intercooler would freeze?
Radiator freezing is more likely, even fuel.
So if you have a hard time starting the other practice is, to start the car with throttle wide open. if it starts then, you should check the injectors for leaks.
checking injectors for leaks? remove the fuel rail and turn KOEO look for drips or fuel period. BTW base fp is 43.5psi, no vacuum. With vacuum can vary but should be around 36.5psi

It's beginning to look like a mafs issue, code check may confirm this or it could be the wiring.
so check those codes
The other issue is what i call maintenance, but it's just common practice for me.
Checking base timing and base idle.
Since you're having a issue with running with the IC pipes connected, 1 trick is to open the iacv all the way up, only if there are no injector leaks and the car will stay running with the pipes connected. Let it idle\warm up get timing light, set base idle and check timing in timing mode.

I could speculate or continue with guesses, but you should start with a code check, even the tps voltage could be set wrong. so check that as well.