Need Help 91 Mustang

The car is running like crap ever since I rebuilt the motor. The motor is good just no power its cuts out it u try to rev it up. For one problems and the other is on a drive feels like I hit a break wall at 2000 rpms and no power but revs up slow and just makes sound only happened after I clean the salt and pepper shakers
plus I'm not getting a code 11
I'm completely lost on this lol thanks for any help if anyone got any idea