Idle probs
 

I bought my truck in 2001. Shortly after i had issues with it stalling. Initial start up would be fine up, but when the truck warmed up the idle would be non existent. So basically the only fix i did was adjust the idlle up so it would idle at 800 when warm. But now when at initial startup the idle ranges from about 1500-2000(depending on the temp outside, summer =1500ish, winter=2000ish)then it slowly creeps down to normal linearly when the engine temp reaches normal. Winter is starting once again and it tends to climb even higher slightly above 2000. So ive decided I want to try to solve this and abandon my if it aint broke don't fix it solution. Many people in the past have told me this is normal but i refuse to belive this. Thanks

I guess i forgot to ask a question. This isn't normal right? What could it be?

my truck idles at 1700 whens its cold then when it gets warmed up it idles at 900