Hello, first, don't guess at any particular part until you have a diagnostic test performed on the evaporative emissions system. Is the emissions test saying that the diagnostic monitor for the evaporative emissions system is not set? This could be an indication of driving, not so much a problem. Hard to say without hands on analysis and needed testing.
See this article about drive cycles in relation to emissions testing:
https://repairpal.com/drive-cycle-issues
Here's a link to find some shops near you:
www.repairpal.com/repair-shops
RepairPal Certified shops can diagnose and repair your 2007 Kia Amanti. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.