tps should be 0 % at idle and 100% at WOT. otherwise, it is either in need of adjustment or replacement.
Regarding iac position, i can not really comment, ask Xulfiqar for that.
I think idle issue is usually a bad tps or dirty/bad iac.
In your case, i suggest to atleast spray some carb cleaner + wd40 into iac or dismantle and clean it. then recheck.
My experience meanwhile, do not remove throttle for no reason, do not open those special head screws, they are not supposed to be open. if your throttle is good, maintain it with carb cleaner and wd40 once a month (in fitted position)