my xj has started sputtering out recently,espesially when its been driving down the road for 20 to 30 minutes,but when ever youve cme to a complete stop and barely hit the skinny pedal and then it just dies,i replaced the feul filter yesterday and it helped a little bit,but bsides starting off,it wants to sputter from the 25-45 mile an hour range,i know for sure its not the trans,and ive ran about 2 cans of sea foam threw it,but tht hasnt helped at all,does anyone have any idea of what this could be?and ive also replaced the spark plugs about a month ago,i would greatly appreciate the help

 

Check out your fuel pressure.