Live in Phoenix and it is hot but, when A/C is on the temp gauge is always at 125 to redline. Also after driving for 30 minutes ar so I have noticed the top radiator hose is collapsed, like is is creating a vacum. I can take the filler cap of and the hose goes to normal. I have replaced the radiator and thermostat. Also after driving without A/C the car still seems to run hot 100-125. Does anyone have any suggestions.

Thanks in advanced for your help

Michael