Originally posted by Redcivic
No, the radiator is a year old. The guage gets almost to all the way hot, it does not actually biol over or anything? So coolant temp. sensor?
what makes you think it's the coolant temp sensor? if the fans come on at idle, it aint the sensor.
it could be the sending unit, but highly unlikely.
besides, you said it overheats on the highway, but doesnt in traffic. that's backwards of any car with a cooling system problem, but it's parallel with a car with a blown headgasket.
the air rushing into the grille at 60mph should cool the motor reliably. only when you're in traffic could the fans come on, as there's no air rushing over the radiator to cool the motor. sinc the motor isnt overheating in traffic, but overheats with a load on it, it sounds like you probably have a blown headgasket or other severe cooling system deficiency... not a sensor malfunction.