My 1983 Oldsmobile Cutlus Ciera, 2.5L four cylinder has a cold starting problem. When cold only, after starting, the idle will surge up and down and up and down continuously. If you put it in Drive it will smooth out immediately. Put in back in park again, and it will surge. Once the engine warms up it smooths out and is not noticeable. I have unhooked the battery and when the computer resets itself it seems to fix the problem for a day or two, then it returns. Any ideas? Coolant temperature sensor, Idle air control motor? I can't seem to figure it out. Thanks for the help.