My LG4 has a single electric fan. It has started to over heat which I think is because of either the Fan Relay on the fire wall not working or possibly the 160 thermo going out. I have noticed that the operating temp has shot from 160 - 180 to over 210. The fan never comes on which makes me suspect the relay. What do you guys think? I am getting lot's of bubling in the overflow tank and some slight "knock or ping" when I drive. Need to solve this right away. can you help me go int right direction?