Hey team, so I’ve just bought a 99 mitsi mirage. The previous owner has disconnected the coolant hoses to the heater (connected them to themselves) I want to hook them back up but there are three penetrations from the firewall, I hooked up to the two that I thought were the correct ones as they looked the same and just seemed right. Turned the car on and a very slow dribble came out of the third one. But if I hook up to the third one then it pours out of whatever of the other two aren’t hooked up. What I want to know is either am I doing something wrong or can I just blank off the 3rd one that is dribbling

thanks