Sometimes when starting my 2006 Ford Taurus, it hesitate to start, sometimes it does this and sometimes not, what could the problem? I'm thinking the starter. I replaced the battery, thinking it could be the battery, but the problem still exist. Help!

Replace the platinum spark plugs, with the exact Motorcraft plugs that came in the engine, if they have not been changed in 50,000 miles. Being a V-6, many people neglect doing this due to limited access to the rear plugs. The Trick in this link may help:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-8.html#post1375876