Not sure if this helps, but my brother just experienced simular problem with his Range Rover. Ended up being the collant sensor. The sensor was not working and the computer was flooding the engine and the truck would no start. Sounds like there could be a sensor gone bad and your computer is not regulating fuel and air flow properly.
A guess. When ever trying to figure these types of problems out I always think of the four basics, Fuel, Air, Spark. You need all three and without one the car will not run. Try to elimate one at a time. Make sure you are getting spark, you should smell fuel as the car would probably be a little flooded at least, if the pump and injectors are working.