Car engine gets too hot

my tiburon keeps over heating. i thought it was a coolent problem but when i filled it up and made sure it was not leaking it still heats up. if i keep the heat on full blast it seems to regulate itself but i end up roasting. can anyone help me out?

Install a new thermostat and see if that fixes the problem.

If the thermostat is not opening fully it will cause overheating.

Thermostats are not expensive, and replacing one often falls into the DIY category of car repair.

Check to make sure radiator cooling fan coming on.

“when i filled it up and made sure it was not leaking”

So are you saying that you were low on coolant? So you refilled and found no leaks?

Pull your dipstick and have a look at the underside of the oil cap. What does the oil look like?

Beyond cold engine warm up are you blowing any smoke out of the tailpipe?