Stomp! And Bang (back Fire).
 

GUYS! I JUST INSTALLED COLD AIR KIT, HARMONIC BALANCER, AND REMOVED POLLUTION PIPE FROM THE BACK OF THE ENGINE. AFTER TOOK THE CAR FOR A TEST DRIVE, I NOTICED THAT WHEN I STOMP ON THE GAS PEDAL WHEN DRIVING SLOWLY, THE CAR SEEMED OUT OF BREATH. I MEAN, INSTEAD OF LEAP FORWARD, IT JUST STALLED AND BACK FIRE. IF I SLOWLY STEP ON IT, THE CAR WOULD HAVE NO PROBLEM PICKING UP ON THE SPEED. BUT EVERYTIME I GUN IT OR DOWN SHIFT TO PASS, THE CAR ACT AS IF IT RUN OUT OF AIR. I PLUGED BOTH AIR PIPE HOLES ON THE BACK OF THE ENGINE AND CHECK FOR LEAK THERE BUT CANNOT FIND ANYTHING. THE CAR WAS FINE BEFORE THE CHANGE. NOW, THIS IS WHEN YOU GUYS STEP IN, SEE IF YOU CAN HELP ME OUT, PLEASE.

vaccum
 

did you plug the vaccum lines that came out of the smog pump? Have you ran any codes? Have you run used any starting fluid to check for leaks. Could you of messed up a spark plug wire when removing the smog pump? Did you remove the smog pump?

Mountain Main

Mountian Man, yes, I plugged both of two holes in the back of the head, no, i have not run code scanner just yet, yes, I removed smog pump ( long time ago ), no, I have not check for vacume leak yet and I do not know if I mess up the plug's cable. I will try to do things that you suggested, Thank you. If the problem still there, I will come back and challenge your brain again.