I have a 1997 Ford F-150 4.2 L and the engine will start but will not completely turn over. I have replaced the fuel filter and I replaced the fuel pump relay but is still doing the same thing. Fuel pump kicks on but nothing. I think it might be the fuel pressure regulator. Any suggestions?

 

A 1997 should be storing codes. Do you have a code reader, if so, what are they? Might invest in a code reader if you think you'll be doing work on any of the newer cars in the future. Well worth the bucks. Hard to say what the issue is. It can even be a bad solenoid switch.

 

Start over again and describe what happens.
What you said in the first post makes no sense. (Starting and no turn over)
Going at any problem by guessing is not the way.
Good luck.