i have a 93 2.3L auto with 146000 miles on it, and like the past week/week and a half not sometimes when i start my car when i put it into drive the car wont go past 2000 rpms and wont go past 15 mph but once i hit the breaks and accelerate again it will start going normal. when it started doing it it did it and then didnt happen for a few days but it has gotten more frequant. all my fluids are topped off and i keep regular matnace on the car done. if anyone can tell me whats going on i will be thankful.

thanks
chris