RepairPal Certified shops can diagnose and repair your 2003 Oldsmobile Alero. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
https://repairpal.com/drive-cycle-issues
That's a good starting point.
Each vehicle has different requirements; I'd suggest highway driving at 55-60 mph for a sustained, steady period is one important bit to consider.