Engine stalling issues

[FL911]

I have an 02 911 Carrera C2, just did the RMS and IMS update, battery was disconnected for 3 weeks or so.
Finished up today and took it for a ride after topping off all fluids. Everything was fine and after returning from a trip of about 6 miles, I was on my way back home and at a stoplight it just starting idling like crap and died.
Got a push into a parking lot and checked everything out, no leaks, nothing was wrong.
Started back up after about five minutes or less and got back home. Looked everything over, let is sit for about 15 minutes, made the same trip and it did the same thing two times on my way back.

Any thoughts on what this might be, never did this before. And I am desperately wanting to drive this car again.

Thank you for your help.


Frank