Fix my old car or buy a brand new car?

I am in my final year of college and I have a 97 plymouth breeze that i bought for $1200 and it has 135,000 miles on it. Lately it has been sputtering and it actually died out today in the middle of the road when I had just got it fixed(catalytic converter, new oil valve, and spark plugs) like 3 wks ago for $500, then other repair cost added up to a $1000. I am getting sick of fixing this car and something always needs to be fixed, So do you think its cheaper to to invest in a new car I am going to purchase a new on in May 2011 ,but I don't know if its worth the wait with all of these repairs taking place??? I have been looking at the Honda Fit for $13,000?