I have a 2000 Automatic Jeep Wrangler Sport. For quite a while now it would have a "hickup" and the tachometer would drop, then it would go normally. Recently it has stalled several times going full tilt down the road and when the key is turned, it has power but won't turn over, nothing. I was able to get it to start one time by playing with the starter relay and by jumping a couple of pins in the relay with a wire.. I've brought it to the dealer but when it gets there, driving or by tow truck, it starts fine and they can find nothing wrong. I just replaced the fuel pump and it stalled and wouldn't start less than a mile from the dealership. I've put in new battery cables, replaced the starter relay, but to no avail. I'm confused. Any ideas?