Q: My upper radiator hose is hot and my lower radiator hose is cold ..my car is also overheating and my radiator fan is not on

asked by on July 21, 2017

My car is overheating my upper radiator hose is hot but my lower is cold and my radiator fan is not kicking on.. Help

My car has 225000 miles.
My car has an automatic transmission.

It sounds like you may have a faulty coolant fan relay. The coolant fan relay helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this relay is not working properly, this can cause the fans to come on intermittently, stay on all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. The other possibility may be that the radiator may have some blockage as the upper hose is hot and the lower hose is cold, indicating that the coolant may not be ciculating properly. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.

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