What could make my car die when going into closed loop?

[VeesGN]

My car starts and runs fine for a couple of minutes. When it changes from open/close loop, it runs terrible and dies. No codes, readings are normal until it dies. What circuits are activated and might cause this to happen (O2 sensor or ?)?

Most parts are relatively fresh on the car.

 

[blackbuick87]

First thing I would do is reset the IAC and TPS

 

[TurboDave]

Also, monitor your BLM's and especially INT's when it switches over. If either/both of them are at their limits when this happens, it could be that the "tune" is so far out of whack that neither can compensate.
Sounds like it's going WAY lean, so when it switches to closed loop your BLM and INT are probably both hitting 150+