rough idle when cold or lot of moisture in air
 

can anyone help me ?
01 F250
in the morning when its cold i start it it doesnt run
or idles way lower than factory pcm settings
i rev it to 2,000 rpms for about 5 to 10 mins
and it ok if i let it sit for more than 5 hours i have to repeat the process
now i thought maybe could be the IAC valve however if it was my IAC valve my
check engine light would come on ... however no light on at all so im alil confused
and dont want to throw parts at it lol so any help would be awsome thanks !!