2000 Cherokee Sport mileage: 57,000. The starter will crank, but the engine will not fire up for a few seconds, or not start at all on the first try. The dealership said that there was a bad fuel sensor. We had sensor replaced and problem persisted. The dealership had us pay for a fuel system cleaning, which did nothing. The dealership then replaced fuel pump, saying that the first one was definitely bad, still no change. One week later, nearly 7,000 miles since the problem began, they put a third fuel pump in, saying that the second one had gone bad. Again, there has been no change whatsoever. It seems as though they can't think of any other solution. Do you have any ideas? We want to make sure the problem is fixed before our warranty runs out. Thank you.