I gotta 97 tour MTX, my check engine light has been on for a while. I finally got both O2 sensors changed. I reset the computer and ran the car, the car shifts hard and stutters between 4500 and 5000 rpms after that it smooths out. Need some help on trying to figure this out, I think it might be my MAF. What do you think?

thanks

97 Contour GL MTX
K&N Intake
Artic White Lights
Blue Stobes
Kenwood KRC-508S head unit
Kenwood KDC-D300 11 Band Spectrum
Analyzer CD Player
MTX RT-2120
12" Polk EX