2001 Oldsmobile Alero Car Stalling at 40mph and high rpm's

My car stalls around 40mph and it doesn't want to go any higher and my rpm's rev up pretty fast. Also when I start it up, it cuts right back off the first time. It doesn't seem like I am losing power anywhere else. have a brand new fuel filter and oil change. I had tune up last year and a new tranny 5 years ago. I also replaced my cat 4 years ago. What could it be????