One problem related to fuel pump has been reported for the 2004 Jeep Wrangler. The most recently reported issues are listed below.
Vehicle stopped running while driving locally. Steering and braking became difficult. Could have been dangerous at higher speed. Diagnosis by a local mechanic (superior collision & auto service, gardnerville, nv 775-782-2966) was an internal short in the fuel pump module which caused the fuel pump to stop operating and the engine to quit. The fuel pump module is located inside the fuel tank, in the direct presence of gasoline and gasoline vapor. Upon examining the fuel pump module the mechanic determined that the wiring leads to the pump unit had shorted against the module's aluminum housing due to chafing of the wiring insulation on the edge of the housing. They and I believe that if this short had caused a spark it could have ignited the fuel in the tank, causing an explosion or fire. I have owned this vehicle since new and this part had never been serviced or replaced. It was as installed at the factory. To correct this the mechanic installed a new fuel pump module. He said the wiring on the replacement module appears to have been routed more carefully to avoid this problem. I have the faulty module in my possession.