I *think* my '98 V70 is leaking coolant, but im not entirely sure. I just rerouted the cooling system around the heater core because it blew up after leaking into the floorboard for around 3 years. Its no longer leaking into the car, and the heater hoses arent leaking that I can see, but there is either spillage (my fault) or a leak behind the passenger side front tire. I also have been made aware that the expansion tank has a leak in the small hose that runs into the top of it, its actually broken almost entirely and looks to have been glued in the past. Perhaps all the coolant is coming from here? Im not sure, anyone have any diagnostic ideas?

 

I'd start by replacing the broken expansion tank.