Coolant system problem

Hi and thanks for taking the time to read and reply to my post. I had the upper radiator hose had a small leak and my 1993 v6 camry LE overheated while I was on the freeway. Since then the coolant Is leaking out of the overflow tank. I constantly have to refill coolant. When I am engine is at idle it will overheat. However if i touch the gas it will cool off. There r no visible leaks other thatn what is coming out of the overflow when it is driven. The thermostat and hose was replaced when the car got hot. The radiator is about 2 years old. I really dont know what the problem could be...If anyone has an idea please reply to this thread thanks...

Replace the thermostat
Check the water pump
Pressure test the radiator



Does the cooling fan switch on to high speed when the engine is up to temp?
The repalcement radiator, does it have a radiator cap installed, or does it not have a cap?