My 2003 chevy cavalier temperature gauge turned all the way over and will not go back to normal position. I think its broke, I dont know what happen. The car will not start. I went to autozone and got a temperature sensor to replace the old one. I am having a hard time locating where the sensor is located. The guy told me it is located behind the alternator. If someone can help me to locate and how hard this is to replace and why the guage stopped working. I would appriecate any advice . thanks