97 buick skylark stalling

I have a 1997 buick skylark with the 2.4 liter engine with approx 125K miles. After I drive the car approx 30 miles on the highway and get into a town, the car will idle fine at a stop, but as soon as it is given gas, will stall. It will start right back up and sometimes run fine till I stop again and sometimes die again. The computer is returning a no codes/pass when scanned. This has happened the last couple of days now. It also seemed that if I kept accelerator pressed a little that it would accelerate normally. After the car sits a few hours it will drive normally again. Any ideas would be appreciated. Only thing I could think of was a throttle posistion sensor. That something that it could do?? any help is greatly appreciated.

You might try cleaning the throttle body, and IAC motor. As the engine ages, deposits are left on the small orifices on both surfaces, changing their clearances. The result is that the system cannot determine the necessary adjustments. Ray

I did happen to clean those things up. Also changed the throttle sensor at the same time. So far so good. Have had even colder weather since then and no further problems. IAC was somewhat gooped up so that may have been some of the problem as well. Thanks for the idea.