94 altima tends to hesitate sometimes

hey all, i recently replaced the stock spark plugs on my altima, that went fine. i also replaced the wires on it, and had made the mistake of not using anti seize on the plugs so my wires would pop. fixed that, now its fine. however, recently the car has been hesitating on me, especially in teh first and second gear (i have a manual), and only when i apply too much gas. i had comented that the wires are fine now, because the car seizes almost like when my plugs were popping and therefore, not firing. now the wires are sitting fine, it idles fine, the plugs are good... and in third and fourth, i can floor it and not hesitate, although i dont accelerate well when i floor it. what do you think can be causing this? thanks alot.