Oldsmobile/Buick Repair: lumina idle, chevy lumina, air control valve

Question
i was trying to contact you so many time before but you are all the time maxed aut .but anyway hi my name is enes im volvo mechanic i need some help on my car chevy lumina 3.1 91000 miles  i had itermittent  problem high idle  stays all the time around 2000rpm-2500rpm  sometimes it help if you cylcle the key off it goes to normal but it comes back to high idle .no dtc in car so i replace the idle air control valve it was good for 1 day than it came back again so know it is intermitten problem it run's good 4-5 day's than just when you drive the idle stays high or when you start the stays high until it stops 2-3 days. maybe it is the coolant sensor i thing or the pcm  or what do you thing to check thank you

Answer
hello
how you doing . Your problem is in the pcm . Take it to a good chevy shop and they can make adj on the idile threw the pcm . on that car if it was the colinit senser it would stall the problem again is in the pcm . need more help just let me know . please rate my serivice pete