weird idle problem

[JayDubBlazer]

I took my truck out to day it drove witha very high idel I finally stopeed knocked it down to about zero tension on the screw. I took it on th interstate and and parked it for about 45 minutes. I came back out and and couldn't start it becasue the idle was so low. I opened the hood and truned it about 4 times just to get it to idle regularly and drove it home.

It did this to me last week. My alternator was cranking out to many amps and at the time I had the the idle screo all the way out. Changed the alternator and had to raise the idle again.

The only thing I can think of is that the electric choke could be off. But it was open when it was warm so i don't know

It is a 1406 edlebrock with a edelbrock intake, gm crate with hooker comp headers. Thanks