Engine not starting

I have owned my car (GT model) non super charged for about a year now and recently It began to act up. It would start sometimes and drive normally but when I would go to turn it back on it would crank but never turn on. Coil module, fuel pump, and fuel pump relay have all been changed. There is fuel pressure and there is spark on all plugs. Fuel pump will prime. Both times that it happened I turned my car off on a slope, once reverse parked and once parked normally. And yes it has enough gasoline. Engine will start with either but will not stay on. One of the mechanics I talked to turned it on by simply sticking a screwdriver in one of the spark plug wires and grounding it, after it happened again I attempted to do the same with no luck. I hope you are not as confused as I am on this. Thank you. Before this the vehicle had no problems or noises everything was always checked and it had a tune up four months before it stopped working.