Nothing illegal or hazardous was found on board, Myrtle Beach Online reported.
The passengers finally reached their destination around 4:45 a.m. Friday -- about five hours later than the scheduled arrival time, according to Flight Aware.
A Spirit Airlines spokesperson told Fox News the source of the odor is being investigated.
"We apologize for the inconvenience this diversion has caused," the statement read. "At Spirit Airlines the safety of our guests and crew is paramount."