HESITATION PROBLEM NEEDING HELP again

[Route 66]

I now have the vacuum leak fixed. It idles good.Thanks to the help I got from GOLDCYLON and some others on here.

Now Im working on a very slight hesitation if you try to accelerate quickly it hesitates slightly at the start of a quick acceleration, If you accelerate normally it work's ok... It was there before I replaced the injectors. I think it might be a sensor but not sure. I don't drive the car much so I can't remember how long it has been doing it. You have been great about giving good info in the past I hope you don't mind me asking again...................Thanks ..E