I have a 2002 f150 xlt 4x4 4.6l and about a month ago it started acting up and would not start. When you turn the key the engine turns over but does not fire. I have been all over the forums trying to find a fix for this and have come up empty. So far I have changed the fuel pump relay, can position sensor, fuel pump, fuel filter and the problem still exists. When you turn the key to on the theft light goes out like it always has and nothing else really points to any one thing. I would greatly appreciate anyone's help because we are going into the snowy season and I have a new baby boy on the way!!! Thank you!