just parked it im assuming it ran before you parked it? I would start by making sure you are getting spark and fuel, so test the injectors, fuel pressure, injector connectors, and ignition packs. I would say that is a good start to see whats going on and would say thats most likely going to be where your problem lies. Hard to say but it could be injector failure or something as stupid as a plug isnt connected (may not apply here).
If you need to know how to do this all use the search or better start off in the FAQ and tech section. People will tell you here to look before you ask because everything has been covered here but look first and then if you still are having troubles finding something ill help you or someone else will.