One problem related to automatic transmission control module has been reported for the 1998 Jeep Grand Cherokee. The most recently reported issues are listed below.
Vehicle entirely stalls without warning at idle or very low speeds. Jerks and flashes check engine light for one second occasionally while driving at normal road speeds. Happens multiple times a day under no specific conditions (cold, hot, wet, dry, etc. ) intermittent problem so codes cannot be detected. First occurrence was in heavy mid day city traffic in the middle of a turn. Could not be restarted from park for 10 minutes, blocked entire intersection and entrance to plaza. Was almost hit by oncoming vehicles multiple times. Has the potential to be extremely dangerous if this happens in traffic as it has before. Bought used. Appears to have had pcm, air filter, plugs and wires replaced. Stalling issue is obviously extremely prevalent amongst this vehicle and must be addressed by the responsible companies before someone is killed, likely before more people are killed.