Pressure from the radiator is excessive

I recently know noticed that my radiator cap was leaking when my fluid got to warmer when I stop the vehicle. I've been driving for approximately a year without any problems. I tried to drain my radiator fluid and replace my cap with a new cap but the pressure buildup blew off one of my radiator hoses. I reconnect the hose and put the old leaky cap back on it runs fine, it doesn't overheat. there's nothing in my oil, but there's still a problem. could you please help me? thank you