04 Jeep Cherokee won't start. It clicks when I try to start it.

It sounds like you do have a relay problem try switching relays around that have the same part number start with the starter relay when switching the make sure the key is off each time

Check fuel pressure at injector rail.
Do It Yourself Diagnosis and Repair

Could be a failing starter or problems with the cables.
A dead cell in the battery will do it too.

change the wires that go to the starter i had the same problem fixed now with no problems

I'd look at the crank sensor, this is a 4.0 correct?

Fuel pump

I've got to be reading this incorrectly...You are driving, the engine turns off...you pull off the road? And then without touching the key the engine re-starts, but you haven't touched the key? Or, sometimes you need to sit there for a few minutes and then turn the key to start it?

Check the starter seolonoid, sometimes it clicks that way indicating worn contacts. Have it replace.

you can test your signal wire to the starter by having someone turn the key to start while you put a test light on the signal wire at the stater.If there is no signal on the light then there is a problem with the sending wire from the ignition.

You might want to start by replacing the crank sensor first.