98 ford taurus overheats/brown coolant

My sister has a 98 Ford Taurus that leaks coolant right out of the coolant cap when the car heats up. It boils/steams out of there. What is weird is that the coolant comes out looking like it is all rusty. It is an orangish brown color. Is there anyone who would know what is happening, or who has had this problem?

I think you’ve found the problem. The rust inhibiting chemicals in the coolant have broken down. The radiator has become partially plugged and can’t dissipate the heat. A thorough flushing of the cooling system, new antifreeze and probably a new radiator are needed at this point. You should also replace the thermostat for good measure.