I have a 98 accord ex 2.3L VTEC 2dr, with 225,000 odd miles on it. Earlier this year I was just plowing through coolant, and overheating. Changed the radiator and everything was fine.... for 3-4 months. Now after driving even short distances, my temp gauge reads normal, but the radiator is boiling. My initial thought is that the thermostat is blown, but after reading some of the posts online, I wonder if the temp sensor may be the cause of the problem. Any thoughts?

 

Could you be more concise...."Radiator boiling"?

The system does run at a temperature above 212 degrees however the pressure in the system actually raises the boiling point.
So if you remove the radiator cap from the hot engine the coolant will indeed boil.