My car overheats when it is driven for an extended period or if it's really hot and it's idles in traffic. It does not actully get into the red but it runs hotter than normal. As soon as I park and turn the engine off all the coolant leaks out. It keeps happening over and over. I have replaced the water pump and radiator in the last few years. I've had all the hoses checked and had the thermostat changed out. There coolant doesn't leak out it all pours out as if something has busted but once the car cools down and I refill the coolant it might not do it again for a week or until whenever I get caught again in a little traffic. Help, can't afford the coolant bill!