Sputtering and power loss

'90 XJ/4.0L/AW4 was having problems sputtering on acceleration, acting "bogged" down in the 1200 - 2200 RPM range and dyeing going around corners (regardless of how much fuel was in the tank).
I have changed the fuel pump (whole assembly-strainer, sending unit) and put on a new fuel filter.
It seem to run fine for a day then now only after running for about 30 minutes it is sputtering acting "bogged" down in the 1200 - 2200 RPM range again. Although it is not dyeing going around corners.

Any ideas?

:repair:
Can somebody help a brotha out?

pair8hd said:

:repair:
Can somebody help a brotha out?

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How is your idle, what RPM?
Does the idle rise and fall in cycles of a dozen seconds or so? When the motor is hot.
Does you motor, tach above 3500 RPM, when driving on the highway?
I can´t really picture the 90 fuel pump, does the hose from the lid to the pump, come with the pump? Heard more than a few guys, with later model XJ´s (95-96) have that hose fall apart or flake off.
Have you done a fuel pressure test?
Every time mine dies going around a corner, I check the EGR, but it sure shouldn´t affect your driving at 2000 RPM.
Do most of your problems seem to be at a certain throttle opening, like 1/3rd pedal?
Have you looked at a plug, to check the color. Bone white is often lean, there should be a color or tint to it. They might be lite, if you´ve just come off the highway.
City driving usually darkens the plugs up some, from tan to middle grey. You don´t have to check them all, someplace in the middle thats handy, just one or two.
A lot of guys would say check for a plugged Cat. I´ve never had that problem. Though I have smashed a few to death.