Does yours cut out completely? Mine never actually dies. It idles rough and wont actually go, ten suddenly it will go again. Its either fuel or ignition of some description I am sure. Neither fit perfectly though.
If it were fuel, wouldn't it just die? And why would it smell rich?
If its ignition, why is it intermittent? and wouldn't me keeping my foot to the floor flood it?
Sound like a failing dizzy? Fuel Pump relay playing up?
I'm so lost on this one. You definitely sound like you have a loose connection of some kind though!
EDIT: done some reading an pump relay failure and it seems to fit the bill, so I'll try that first