Looks to me like Gilly has the answer you are looking for. I have read through the thread and at no point have you mentioned that you have performed any tests on the throttle actuator. You can test the resistance of the Idle Speed Contact, Wide Open Throttle Contact and both Reference Resistors for integrity. When checking it with an Ohm Meter you may discover that the ISC-circuit in the Actuator is "Open."

Engine harnesses are known to deteriorate. The actuator harness suffers the same fate only it is concealed by the exterior sheathing on the actuator pigtail. A small incision in the sheathing may prove beneficial in your quest to discover the cause of your stalling problem. If it is the actuator you will want to replace it before it takes out the “ISC/CC” or “ASR/E-Gas” module.

If you need some info on testing the actuator values let me know.