Hey i have a 1990 integra with a b18a1 and in first gear start ups it hesitates. If i really put my foot into it it almost stalls, and then the revs get up quick. The performance otherwise is great (for a almost stock integra). I cleaned my idle air screw as well as my throttle body, intake and injectors. I put new plugs, wires, cap, rotor, and O2 sensor in. I rebuilt the head (no performance on top end) and it has an cai and exhaust. Any idea's of what this could be?