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Q: Temperature fluctuates up and down

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cooling fans work but temperature gauges raises up to hot then back down to normal then temperature rises again then back down... back and forth I have changed thermostat is it a fan relay or a controller

My car has 105995 miles.

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. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.

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