94 mustang staying started problems..

Hi, i just put a new engine in my car, its a 308 with a E303 cam in it. To start it up i have to keep pressing the gas for it to stay started. Everything is hooked up right but still don't know why this is happening... If there is anyone that could maybe give me a few ideas to what the problem could be that would be great.. because im out of ideas lol...

Have you tryed to set the idle at the throttle body?

Where would you set the idle at.. People tell me I can't set idle on my car, me and my dad think we can, but where is the idle thing to be set... sorry I'm new to this lol

I 3 little pieces of cardbored under the idle and it idles at 1000 rpms just have to figure out how to get the screw to go down , thanks for your help, I was starting to get worried

Ok... this is what is going on now, when I have the car running and get the car warmed up, and turn it off, then start it, the car just shuts off, guy at ford said to put a new idel air control sensor on it and I did but still does it lol... is there anyone that could help me.... thanks for your time and help

Ron