91 Ranger over heating

While driving the temp gauge says that the temp is in the normal, but once I get home and turn the engine off you can hear the water boiling over into the overflow tank. Today it a little steam came out. If I turn the heat on sometimes it helps (I replaced the thermostat not long ago cause there was no heat coming out). I've also flushed the radiator several times. Any ideas why it is over heating? Also my air doesn't work. There is a leak in one of the hoses.
The drive home from school is about 40 miles.

Sounds like your temp. sensor has failed you. Check to see that your radiator and/or heater core are not plugged and that your water pump hasent started to seize. Good luck.

I had a friend say that his car was over heating and he took it to the shop and they just took the thermostat out. Could that help??

I don't think the temp sensor failed on me. I've also replace the water pump maybe a year ago or so.

Very well could be the problem. Replace it with a high degree thermostat. This would be a cheap fix, cross your fingers!!

Boy, does this sound familiar... 91 Ranger 2wd, 3.0L V6, 5-speed. Water pump failed 3 years ago. Replaced pump, hoses, thermostat and belt. Whenever the outside temp is above 90, she boils over after shutting down. Flushed everything, new thermostat - no change. In June, got fed up and took out the thermostat. 10 minutes - Problem fixed. Plan to put it back in at the end of the summer. My theory is that the opening on the replacement thermostats is too small (unfortunately I don't have the OEM 'stat to compare) They just don't let enough juice thru when it gets hot. HTH.