Momentary rough idle???

93 Grand Cherokee 4.0L has momentary rough idle which last usually less than a second then idles normal a few seconds and then will rough idle momentarily again over and over. Sometimes I wonder if it is going to stall. This scenario continues as long as I am stopped. The engine performs flawlessly at all other rpm ranges. All thoughts on this are greatly appreciated.

First thing I would do is to clean the throttle body and the IAC motor on the rear of the throttle body. Another thing to look at is the fuel pressure at Idle should be arounrd 49 lbs. Could be a bad plug, wire even a Injector. The IAC is prone to idle and low speed stalls when dirty and when going bad. A tooth brush and carb cleaner, starting fluid work well. Did you have a check engine light on?

No, I do not get any check engine light. I just installed brand new plugs. I will check throttle body and IAC motor and see if that helps. Thanks