1992 Toyota Paseo Anti-freeze boiling out of overflow tank

Hi N173218. Welcome to the forum. This sounds typical of a leaking head gasket. The test that should be performed checks for combustion (exhaust) gases sneaking into the cooling system. I call it the "sniffer" test. It involves drawing air from the radiator neck through a glass tube with two chambers partially filled with a special dark blue liquid. If combustion gases are present, the fluid will turn bright yellow. That is near positive proof of a leaking head gasket. Find a mechanic with this tool and ask him to test for combustion gases in the cooling system.

Caradiodoc