I have an 87 FJ60. I am redoing my cooling system and discovered an issue. Does anyone know what these are/what they do? I had my engine rebuilt where the shop broke them and instead of fixing them they just plugged them. It appears to be part of the vacuum system but I do not understand why they are attached to the thermostat housing where there is coolant. I have been having overheating issues so could this be contributing to the problem? Any input is greatly appreciated!