I have a 1995 3.1L (3100) when cold the engine hesitates under light throttle if you get into it you can clear is out. As is starts to warm up it goes away usually only happens once during warm up. If you let it sit and cool back down sometimes it does will do it again. Gave it plugs, wires, tps , fuel filter, t-stat. There are no codes present , and uses no antifreeze, but the temp gauge does fluctuate some. Goes up when you slow down and drops when you speed up only has a 7 - 10 degree change when I watched it on the scanner.

i wonder if your fuel pressure is not coming up to pressure fast enough when you first start up the car. Smell any fuel around the engine? Leaky injector "O" ring. Fuel pump not getting up to pressure fast enough or fuel press regulator letting fuel press decay after engine is stopped. Good luck.