Engine cranks but does not start?

If you get in the car push the brake and hit the start button it turns over normal, but it won't hit at all. If you push the gas pedal all the way to the floor and try to start it, it acts like it wants to start but never does. I've put a new MAF sensor, a new crankshaft sensor, fuel filter/pressure regulator, I've checked the fuel pressure it's good, I've checked all the fuses they're good, I've checked the ground wires they're good and I've lost sleep over this because I can't figure it out it'll be the first vehicle that I have had to go and ask somebody else for help. Please help me!