Changed alternator Wont run

[Erronh12]

My Alternaor went out. So i changed it. My bronco II will start but it will not idle and when you give it gas it starts missing. The alternator is charging the battery. Its had 2 advance alt and one from ford. The one from Ford is the one that is on it now. Same problem out of all 3. When you unplug the alternator though and let the truck run just off of the battery it runs fine. Ive had it at two different shops and its still not fixed. Got any ideas

[kirkland2887]

are you unhooking the wire that goes to the battery or the plastic connector