I have an 88 cherokee, and it was "randomly" not starting at times. It would turn over but never fire. It was totally random, but more predominant in the morning when it was cold. Heres how I fixed it.
Dragonking is on the right track in that the crank sensor on this model is typically the culprit of this. What happens is that the crank sensor is so damn ginger on the side of the bell housing that over time it shakes and wiggles slightly out of position. Because the sensor works magnetically and has VERY tight tolerances when it is out of place the teeth on the wheel inside the bell housing do not trip the sensor, hence no "spark" is sent to the ingnition system so, even though theres fuel in the line, there is no signal telling the plugs to fire.
This sensor is a pain in the butt, as it only has to be out of alignment by a micro-hair to not work. Ive talked to many a jeep expert who said this is not uncommon on these model jeeps to happen. Ive found that when it happens to me, I can literally grab the wire harness that runs from this sensor into the engine compartment and give it a slight tug and bingo it starts.
Not sure if thats your problem, but worth a shot.
Friday, March 21st, 2008 AT 5:30 PM