Dude, I had this same issue and still haven't had it solved to this day, Its really annoying and really dangerous especially in heavy traffic when the car stalls randomly.
The best things I have been able to come up with where some kind of ground wire that was earthing out possibly, I also once gave my ECU a shake and it caused it to stall, but then it all of sudden stopped for 3 months, I took mine to auto electrician who didn't plug it in to check fault codes because for some reason he thought not too, i would recommend getting that done.. Good luck if you find a fix definitely let me know if you do, its been annoying me for so long.