apedosmil

I just picked up a 1989 red mustang GT and after taking it home for the first day sent into the shop for a front end reallignment and a new rack and pinon for the steering and noticed on the way home when I was getting on it at about 2000 rpms the car would give out, not like back to idle or it didnt sound like it was gonna die on me, but it just would go through 2,000 rpms weak and then get to about 2,500 or 3,000 rpms and kick back in with power. I think it could either be dirty filters, bad throttle position sensor, or possibly a fuel management problem? Any help for my new baby would help thanks guys!