I have a 2002 Santa Fe V6 auto trans. Living in northern illinois, its sometimes hits -10 f to -20 f . first thing in the morning. The Santa Fe used to immediately go up to 1900 rpms upon startup, and very gradually reduce after it started to get warmed up. IM aware that i need higher rpms when cold, but, it always bothered me having the engine scream to 1900 rpms when very frigid out and not recieving adequate lubrication in time. So, i took it back to the Hyundai Dealer i bought it from and they said :" They range anywhere between 1600 and 2000 rpms, so, yours is normal" . They indicated no adjustment to the cold idle could be done. So...not willing to take no for an answer...i asked my normal car mechanic what controlled the cold idle rpms on the car. He took the device off the engine that was held on by two screws and a push in connector and showed me . Cant remember what he called it, but, he tried cleaning it with solvent and put it back on. Still didnt make any difference. So, i had him explain its operation to me. IN short, it bleeds some vaccuum air thru two ports within this device as a rotating drum either partially covers or partially exposes the two ports in response to a trickle of electricity coming thru the wire harness .
So, for kicks when i got it back home, i took it off and placed some thick aluminum foil tape i had completely over the two ports then punched smaller holes into the aluminum foil tape to simulate 'smaller' port openings. Put it back on the engine , and, wullah ! Now she goes to 1200-1400 rpms when cold which seems alot more sensible than 1900 or higher rpms. It didnt affect the driveability at all either.
I didnt tell you this story to pat myself on the back. Rather, to express my dissappointment with my Hyundai Service Dept. for not knowing (or wanting) to solve the matter. Surely they must know how to remedy this...but i reckon thier hands are tied to what Hyundai calls 'normal design' .