When I shift the car that is just started into gear it seems to idle very rough. When the car is idling and the gear shift is in Park it operates smoothly. The wires, plugs, MAF, and the throttle body has either been replaced or cleaned. I have checked for vacuum leaks and everything seems good, I was just wondering could this be a non-operative or dirty Idle control motor?- Any other suggestions I would be very appreciative
Since you feel it when you place it in gear, have you checked motor and trans mounts to make sure they are in good condition. When you put the car in gear, it puts a load on the mounts and if one is bad, you may just be feeling the engine vibrations.
As far as the IAC, it really only maintains idle speed and wouldn't cause a rough idle.