Lots of potential reasons requiring good diagnostic tests.
Start with the basics like spark plugs and tight connections. I've read a lot about hard starting issues that have been fixed with a valve lash adjustment or new plugs. A compression test would be worthwhile during the effort.
If those things check out, look for things that would trigger a lean condition, like giving the T-MAP a squirt of cleaner. The lack of available scanners makes it difficult to check EFI control sensors like engine temp, TPS, IAC, etc ... so it might be worth a trip to the dealer if the simple stuff doesn't address the issue.