Q: Engine overheating even though coolant fan was running

asked by on October 14, 2016

When I'm driving on the interstate, the temperature gauge hovers around the 3/4 mark. When I get to where I am braking more often. The gauge hovers above the 4/4 mark. A mechanic told me to check to see if the fan was running when it got to that point, which I did and the fan was indeed running. What else could it be?
My car has an automatic transmission.

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This can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch.

As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, 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.

To avoid any unnecessary repairs, I would suggest having an expert from YourMechanic come to your home to diagnose your cooling system.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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