I have a 98 Acura Integra that the heater is not working on. I've replaced the thermostat already, and just put a new radiator in After letting the car heat up some, I felt both heater hoses that go into the firewall into the car, they were both cold, so I'm guessing it is probably my heater control valve. I'm just wondering if you can manually open it up to allow hot water to enter the heating core? And if you can do that, is that a decent temporary fix, and allow the heater to blow hot again?