i'm losing gears while car is running!
 

hi...hope someone can help..on staturday while driving i stopped @ a
4-way and when i accelerated away it wanted to shift from 2nd to third
i just got high revs and the car started coasting to a stop...i can rev
it but nothing happens..no gears....weird thing is when i start it up
again i can gets gears but after a little while gears drop again and
all i can do is just rev....

does anybody have any ideas?