i have a 2000 lightning just bought a diablo tuner and installed the pulley tune worked fine! then i just got a 90mm mass air went to install the 90mm mass air tune and it said saving back up *had already done that when i installed the pulley tune* it wouldnt let me install the tune beacuse said it already had a tune installed and wouldnt work how do i fix this or what do ineed 2 do?
