98 camaro

Hey eveyone...my ride is running like ****, really bad. Between 1500-2000 rpm it just bogs down. I wanna know if anyone has a program/scanner that could take a look and try to find the prob. Its not throwing any codes but sometimes those codes dont pop up on the dash. On top of all this it is running really rich???? I just dont want to take it to a shop and pay 85 to have it diagniosed if i can have someone locally help me out. thanks guys