'99 Elantra Killing/Tranny issues?

My son't Elantra is acting up. When he starts it up cold and heads out it will die at the first stop or two. Also occasionally taking off from a cold stop it will hestitate, almost as if popping the clutch, but this is an Automatic tranny. I'm thinking this could be a tranny problem as it isn't upshifting and downshifting quite right either. He's gov over 90K on it, I'm hoping an auto transmission flush will solve the problem. Anybody else experience this with their auto Elantra? Could it be the whole tranny going? Thanks for any tips you may have.

Hyundai AT are weak, especially if the wrong oil was used OR if it was never serviced ... From what you wrote a flush might not make any difference.

Mine is near 160k and the tranny is starting to act weird, I had a friend that changed his at 90k miles because it was shot, so it all depends on how it was maintained, how the car was drove and if he towed often or not.

For a 99 Elantra I'd say find a low milage one in a junkyard for 100$ and change it ...

So far so good after the tranny flush, but he hasn't driven it that much yet. Thanks for the info.