My 2002 Jeep Grand Cherokee. Will die going down the road. Sometimes it starts back up without me touching the key.other times I have to wait a few minutes before it will crank again.Any suggestions? Thank you.

Could be a sensor shutting off the car, engine overheating, ECU overheating.
You may need to pull codes from the OBD/onboard computer.

Are you sure it's not low on fuel? Any error lights?

Try a repair manual for 'troubleshooting steps'
http://onlyrepairmanuals.com/jeep/jeep-grand-cherokee-1999-2004-repair-manual/

The pump can be running but not pumping any fuel.
When it stops running you will need to figure out if you are loosing spark to the plugs or fuel to the injectors.

The only component I know of, that shuts a Jeep off while idling or driving 40mph down the road, is a bad crank sensor. Usually when it starts going bad, it will sporadically shut off, like yours does. Eventually, it will just die and the Jeep will not start at all. Have it tested and replaced, if necessary.

I have had this happen with the Jeep 4.0 motors because the rubber hoses going to the metal intake from the valve covers had cracks or were broken. Its been a while sine I've been under the hood of a 4.0 but that is a good place to start.

u need a good car electrician to check the faulty electrical circuit that goes on and off at times or have ur car diagnosed electronically using an electronic scan tool to check if ur having a faulty signal from ur relays or your on board computer/ it seems to me the real culprit is ur ignition key cylinder that when not properly set wont give electrical connection to power up the starter....its definitely an electrical issue....

I would check the dealer for any TSBs

replace the crank angle sensor and this should cure your problem

Could be fuel pump. Have you changed your fuel filter?

Hi, I had simmilar problem with my 1993 JGC . I ran out of gas and it would not start until the next day. Then it will start and run until I put the brakes on tho stop and then it will die. It starts right back up. Ended up being the voltage regulator in the ECC/ECM. It is at the mechanics shop right now waiting for the ECC to come in.I will post a follow up.
have Fun,
David C

you might want to have the fuel pump looked at. have the fuel pressure tested at idle and while driving