:idea: I've got another Idea:
There is a little porcelain block mounted to the driver's side wall of the engine compartment called the Ballast Resistor....
Basically, when you start the Jeep, the Ballast Resistor is BYPASSED, so the fuel pump receives 12 volts. Then, when you release the Ignition switch from START to RUN, the Ballast resistor is introduced back into the circuit, and the fuel pump is only receiving 9 volts. This is done to help quiet the pump and to keep it from over heating.
What you need to do is unplug the two plugs from the ballast resistor and place an Ohm meter across the terminals. Make sure a resistance is recorded, and that the ballast resistor hasn't become bad internally, causing an OPEN circuit, and thus no power reaching the fuel pump in RUN :mrgreen:
-Nick :!: