2000 Acura Integra Stepping on the accelerator pedal.

I have a 2000 acura integra ls sedan. After driving the car (say 1hr or two), letting the car rest for about 30min. Then, starting the car, as soon I step on the accelerator pedal (gradually), car does not accelerate for like a second or two. After that brief pause, car then accelerate with a kick. This happens intermittently and only after starting the car.

I've replaced the fuel pump filter, pcv valve, poured a bottle of STP injector cleaner before filling up for gas. And problem still exists. However, I've not cleaned the throttle/choke as of yet.

Any help is greatly appreciated.