If your transmission is shifting too fast out of 2nd then you likely have a vacuum leak.

I used to have a sledge-hammer 1-2 shift and a too-soon 2-3 shift. Very frustrating.

I solved several vac leaks in my CD and the trans finally stays in each gear long enough for good power/acceleration. The 1-2 shift is still very firm (esp when the car is cold) but not nearly as whip-sawing as it once was.