Hi all. I'm a new toyota van owner and new on this forum. I'm currently 2 days into a road trip with my recently-purchased 1988 LE Van down to Mexico from Vancouver, BC. It's running great but I notice that when I stop it sounds like the coolant is boiling. I've checked the level each morning when it's cold and have added about a cup and a half to the radiator, and refilled the bottle as it was almost empty. Also been keeping an eye on the temperature gauge and it has stayed right around the middle the whole time. So why is it boiling? Do I need to replace my radiator? I was hoping all you experts might have some insight into the situation. Thanks for your help!