For the last week now I have been conducting major surgery on my 92 bird. It was running great and then would stall for no reason (like I reached over and shut the key off). After it would die (with the ignition still on) the IAC Motor would start humming for around 4-5 seconds and stop. The relay on the Evap can would click, then the IAC motor would start making noise again, and the SES light would come on while the IAC motor was doing whatever it was trying to do. While cranking the engine over it would try to start when the IAC would stop humming. It would do this sometimes a couple of mins or up to hours until one of the relays up by the fuel pump relay would click.
At that point, it would start fine and run beautiful for (insert your own # here, doesn't really matter) until, yep, it died again. So, after a week of banging my head on the top radiator support, I got it running, so I though I would post and hopefully help out my fellow F-bodies.

So heres what was replaced...

IAC-No Change
MAP Sensor-No Change
O2 Sensor-No Change
Ignition Control Module-No Change
Replaced all the Vacuum Lines-No Change
Relay on top of the Evap Can-No Change
Distributor Cap-No Change
Fuel pump relay-No Change
Checked Fuel Pressure-Good
Checked for Fire-Good when the IAC stopped humming

At this point I was pretty pissed, but wanted my bird running again (daily driver).

I pulled the ECM down from under the dash and reseated the connectors. I tryed starting it again and started right away. As I was getting out of the passengers side to go back under the hood I bummped the ECM and it died. I then wiggled the connectors and it started right back up again. Touched the middle connector and died again. I pulled the ECM out and opened it up to lok for a loose solder connection or something obvious. Resoldered a couple of things but ended up replacing the ECM. NO MORE STALLS!!

So to make a long story short, while troubleshooting stalls, don't forget or look over the ECM for the probable cause. Gook luck!