Have 98 explorer sport 5spd. Why does it hesitate sometime on acceleration?

What is your question?

The problem only does it when accelerating, but not all the time. If i ease into the gas and off the clutch just as easily, she'll pull off nice and smoothe without hesitation. Any other time, she hesitates and sputters a bit. No engine light on or any stored codes. I was told it could be a fuel injector. Have used complete fuel system cleaner every 3000 miles and had the fuel filter replaced as well. What do i do next? Hate to get rid of it, but don't want to spend more than it's worth to fix either. Please help me, thanks.