AutoPIPE Model Boot Freezes

AutoPIPE Model gets stuck on open with "Performing consistency check, please wait..." and computer CPU goes up. Problem never ends until you exit program. Only happens to one model. Have already tried restoring to previous version of model, made changes, saved, ran successfully. The problem re-appears the next day. Have tried having another team member open the model with same issues so this is a model specific problem. What could be causing this?