I love ford an will never stray. That said, my 91 f150 has been quite the headache. I was wondering if i could get some help. Truck wont stay running unless starter is engaged an giving it a little fuel. Soon as i let off the key boom it dies

 

It sounds like, at least for one thing, your ignition switch needs adjusting or replacing. I'm talking about the electrical part of the ignition switch, a few inches forward of the key tumbler. You will need to remove the plastic cowling from around the steering wheel, 2 screws accessible from the bottom side. You will probably need to unbolt the steering column from the dash, simple 2 or 4 small bolts accessible from the bottom, to do this.

 

It’s not really running if the starter is why is the engine is turning. I agree that is sounds like it could be the ignition switch. There is only one electrical part. The other is the lock cylinder.

You could test fuel pressure and run the KOEO self test to check for active and stored fault codes.