[s-cars] Car Keeps Stalling - Intermittent MAFS?

[EB]

Guys,
 
While driving in a heavy traffic last afternoon, the car stalled.  Restarted right away, but would not respond to gas, would not keep rpm's and stalled again.  Looking through the rear view mirror, I could see black smoke.  After several tries, it finally caught up, and ran fine for the rest of the day and so far today.
 
Any ideas what may be going on here?  Can a MAF sensor be intermittent?
 
What are the potential culprits?
 
TIA,
Edward