I had a similar problem with my 96 Grand Cherokee. Stopped while I was driving, would occasionally not start, or be hard to start from time to time. I changed the crank position sensor, and haven't had a problem since. It's hard to get to. Good luck with fixing it. Have you had the Jeep scanned for an error code?
I was driving my jeep and it just stopped. I have a new battery, new ignition coil, new distributor cap with the rotor. All the lights work, the radio, turn signals etc. It makes a whirring sound like it wants to kick over but it won't start. The AAA guy checked the fuel pump and fuel line and they were fine. He looked over everything and said he cant work out what else it would be. Everything else looks good. Someone told me it could be the crank position sensor?? They also said it seemed that there seemed to be no spark getting to the distributor cap (sorry if that doesn't make sense I am learning alot about cars this weekend.)
I don't know what is wrong with it. I don't want to put money into replacing parts that don't need to be replaced. Thanks in advance for any suggestions.