A TBI not idling can be a few different issues:
- a bad engine coolant temp sensor
- a bad pickup coil or worn dist bushing
- a vacuum leak
- EGR valve sticking or a bad EGR solenoid
- a bad MAP sensor
- a bad 02 sensor
- low fuel pressure (should be 9 - 13 PSI)
Do you have access to a scan tool to see what the sensor values are?
//2000CAYukon