The resivour that holds my coolant has a delight little crack in it that causes it to steam and it gets so bad till I have to pull oovver to let it cool down by that time u can hear the water boiling from the resivour and see steam coming from it could it be that my heater core is gone bad. I used the bars leak aluminum to stop it from steaming up on the inside really don't know wat else to do?94 Chevy caprice classic ls