96 manual sunfire turns off going up hill

I just bought this sunfire and it runs fine except when i start it it hardly ever catches the first time, but after the first time i can usually start it the second time. Lately though when i start it it automatically turns off without me doing anything. Today it also turn itself off when i was pulling out of somewhere, i didnt stall it, it just shut off, but when i started it again it started right away. As i was leaving work, i put more gas in thinking maybe the gage was wrong (it said i had a little over a 1/4 tank) then when i was going up a steep hill i went from 2nd to 3rd and the car just shut off....again. And after a few attempts to start i finally got just to have it shut off again in a couple more feet. After i started it again i finally got it up the hill and made it the rest of the way home without any other problems. I really hope someone has an idea as to why its doing this b/c i no nothing about cars

thanks,
Caitlin