If it is fuel injected check the fuel pressure and then make certain the idle air control is clean. if it is plugged, the engine won't idle. it could also be fuel pressure regulator. Did you replace the fuel filter? I'm grasping at straws here. You obviously have spark and air, you're just lacking 1/3 of the equation. The idle air valve is usually located in the throttle body and acts like a controlled vacuum leak that allows the engine to idle.
Take the oil cap off and throw it away, you dont need that.
May as well drain the oil, dont really need that either. Just extra weight, and without that extra weight, you'll gain like, 400 horsepower!
I plagiarized this from DeathCougar