The 05 & 06 diesel powered Jeep Libertys came from the factory with all the fuel lift pump wiring to under the rear seat, a relay, a 10a fuse, and ECM logic to run an intank fuel pump. But the factory did not install the intank fuel pump as they did in all exported models; go figure.
So to install an intank fuel lift pump, all that is required is to change the fuel tank module with one that has the lift pump and install/update the wiring harness from under the rear seat to the top of the fuel tank to supply power to the intank fuel pump.
CARTER FUEL TANK MODULE WITH LIFT PUMP
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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited 
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