i have a 96 jeep grand cherokee with a 4.0 straight 6. the problem im having is the motor idles good and revs great in park or neutral but when in drive i have to feather the gas pedal lightly because if i give it to much pedal or try to kick it down it bogs down and sputters kinda acting like the cat is plugged. i have had the exhaust apart, and the cat is fine, i have replaced the fuel pump, fuel lines and filter, itc sensor is replaced, along with a new coil,plugs and wires, cap and rotor, and o2 sensors. i have cleaned the throttle body and air filter is good. tps sensor seems to be fine also. it is not throwing a code anymore but is still doing this problem. any input would be greatly appreciated!

 

This may sound weird but could it be the alternator? My father had a problem with his CJ one time where it would idle fine but as soon as he let out the clutch it would die. Ends up the alternator was going out and could provide enough voltage above idle to keep the engine running. Just an idea, wouldn't hurt to get it checked as most auto parts stores will do it for free... sounds like you have tried most everything else.

 

What brand of fuel pump and spark plugs did you use? Just out of curiosity