'94 Diamante Stalling

My 94' diamante is stalling on me, but it is wierd. Some days it will run just fine, but others it will stall as soon as I let my foot off the gas. It is happening more and more lately though. I have already tried removing the batteyr for an hour, connecting it back and then letting it run at idle for 15 minutes to let the computer sense the proper idle speed. Someone said it could be a idle controller chip. Where is thay located in the car? Any help would be greatly appreciated.

I also have some slight smoking when sitting in park for a while(say 10 minutes). I have read that replacing the valve stem seals. Should I try that?

Thanks,
idigital

Hello.. I have had some similar problems and found that there could be a few
issues. First i have replaced the idle control valve (found on ebay) located
to left of air intake in engine compartment. Easy to replace... I am now going to replace the oxygen sensor. I think that the 02 sensor is found under care in the exhaust system..near the fire wall..not sure though.. I am still looking for info on this. I also found that a bad throttle position sensor will cause this symptom. Good luck.. Find anything, let me know.