I just replaced the radiator and thermostat on a 2001 Chevy Lumina. I drained the system before starting and filled it afterwards. When I cranked the car and the temp gauge went past operating temp it went down like the thermostat opened properly. I surveyed everything under the hood and checked for leaks. There was one little hose by the thermostat housing going up toward the intake that had a hole in it. I replaced it and crunk the car again, but the temp gauge showed that it was running hot and the thermostat seemed like it wasn’t opening. What can I do to fix my problem and get the car up and running properly.