Monitors won't set
 

My car has failed to pass emissions testing 3 times now. I had a 97 motor put in when I blew my previous engine but the ECU cleared, now it's 5400 miles later and everytime they hook it up, the tester says my monitors haven't set yet. I've taken it through 2 drive cycles and they still haven't set. I'm not sure what else it could be. The dealership thought it might be a relay problem but it's not and now they're saying I could order a new ECU, but they're not even sure if that will solve the problem. I've already gotten 2 tickets for this, help!