So yesterday I replaced the turbo Auxiliary Coolant pump and I noticed that it is making a hissing noise now. I can hear it running (hopefully doing its job) but it is making a noise I have not heard before even with my old one. I also replaced the lower coolant hose that connects to the turbo. I checked for leaks and found none. I bled the coolant system before I started it up so that the pump was starting dry. Is it possible that the pump has air in it still? I even ran the car with the bleeder valve open for about 1 minute and still makes the same noise? If it is airlocked what can I do to remedy that?