Well, thanks to Mitchell On-Demand and their ability to let people save notes for everyone to see I think I've got this thing whipped. The two vacuum lines on the EGR valve solenoid were installed backwards so it would not allow the EGR valve to purge and close when it was supposed to. It would idle perfectly until the throttle was opened and the EGR valve was commanded to open, and then instead of closing when the vehicle returned to idle it remained opened at wherever it was. This was then causing a very rough idle and eventually stalling the engine. Two days ago when I tried to drive it, I made it 2 blocks from home before it stalled. Tonight I made it 4 miles round trip with no issues. I'm going to run it some more tomorrow night just to make sure, but with I wanted to make sure I shared the info. Might help someone else out in the future.

 

We appreciate hearing the "end of the story". All too often we never find out how things worked out.