sorry to say this Canadian brother but yes the 99s especially were prone to craping a head gasket or two as they aged ....that said a slight anti freeze leak evaporating the water out of it on it's way down the exhaust system may leave a yellow substance that probably will freeze in your -20 to -35 air... sure hope I am wrong but if this is not combustion water leaking out of the factory weep holes then you are probably screwed