Why my car is over heating

What year is the Fit?

Most common causes of overheating are a failed thermostat or water pump. Thermostats are significantly easier to replace than a water pump so if you’re going to do it yourself that’s where I’d start. If that doesn’t help, I would take it to a repair shop. Water pumps are tricky and if you don’t know what you’re doing you may end up with the same over heating problem.