1992 Cadillac Seville wont start back up

My car runs great, starts up first time. It doesn't over heat but when you first start then drive it for a little while till it gets warmed up then shut it off. Then right after I try to start it and it turns over but wont start! I leave it set for about an hour or two and then try it and it starts right back up no ploblem. Also sometimes if you drive it for a hour or so especially if it is hot out side then it starts lunging forward while driving and then all of a sudden the tach start jumping and gauges start going crazy and looses power. Then dies and wont start but leave it set and it will start right back up in 2 hours or so? Do you have any idea what would cause this? Thank You!