The car was running fine, temperature wise. It started to get hot and we realized a fan wasnt running. It turned out to be the relay so we replaced it. The car never over heated thankfully. At the time, the heat would work as long as you were driving. NOW the car is overheating. According to the gauge inside the car, its gets hot, over heats and shuts down, then magically the temperature drops to normal. We cant find any leaks, so I figured the thermostat was bad and was pushing coolant out the over flow. Replaced the termostat. It is still over heating and now the car doesnt have any heat at all. I checked the floor board and it isnt wet, so I wasnt thinking heater core. The car isnt smoking but when you turn the heat on it blows cold and the lights dim. I dont think the water pump is bad but its a possibility. What should we do next? The oil/water and water/oil also checks out… so i dont think/hope the head or block isnt cracked.