2001 Jeep Cherokee

Engine Performance problem
2001 Jeep Cherokee 6 cyl Two Wheel Drive Automatic 160000 miles

My dealer is unable to fix the problem on a permanent basis. The check engine light will come on, the engine sputters around 80km with a distinct power loss and knock. At the same time, the cruise control also goes out. If left in this state, the engine will also stutter and knock with the power loss at 100km and the power loss will continue to worsen.
May 30, 2009.

First thing you need is the fualt code, do this.
With the ignition switch in the OFF position, depress the TRIP and RESET buttons.
While holding the TRIP and RESET button turn the ignition switch to the ON position.
Continue to hold the TRIP and RESET buttons until the word CODE appears in the odometer windows (about five seconds ) then release the buttons. If a problem exists, the system will display Diagnostic Trouble Codes (DTC's). If no problem exists, the code 999 (End Test) will momentarily appear. Post all codes displayed.

May 30, 2009.
Hi, I only have a trip/reset button. I pressed and held it as advised - the instrument cluster went through a check showing all the lights at various times and the guages all going trough a number of positions. The odometer showed all 1's through all 9's, then showed the trip setting. Pretty neat. The word Codes never showed up and at the end of the dash test, the engine check light came on again.
I read a number of stuttering, power loss problems for Jeeps and it seems the fuel pump may be the problem.
Any thoughts? Thanks.

May 30, 2009.