Why does my car hesitate to accelerate?

I have a 98 Chevy Lumina, 3.1. I recently have changed the oil and filter. Changed the spark plugs, air filter, fuel filter, I also changed the serpentine belt. Mostly every time I slow down then give it gas it hesitates to go. It's annoying and frustrating! Please help. also I didn't change the spark plug wires when I changed the spark plugs. Could that be it?
Why does my car hesitate to accelerate?
my first guess would have been spark plug wires. so yes definately change them.
Why does my car hesitate to accelerate?
Sound more like fuel problems. Have the fuel injectors cleaned.
check the clutches also!
this sounds more like a fuel problem. if i were you i would put in a fuel system cleaner, you can get it at alot of stores. i even get mine at kmart.
if the plug wires are bad then go ahead and change them but i agree with the others, it sounds like fuel. get a can of throttle body cleaner and clean out the throttle body so it can breathe. take the long nose off the throttle body, take out the screen and spray up inside to wash out the carbon. now once you get done it will be hard to start but just keep cranking and it will start.