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Q: Car gets too hot before the fans come on.

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My car was overheating while idling, but would cool down when driving. Replaced the cooling fan switch and the thermostat, so now the fans turn on. But, now the fans don't come on until the car is way too hot to cool down. I've recently refilled my fluid in the radiator, and I've noticed no leaks in the radiator our hoses. Can you tell me what my next step should be?

My car has 156000 miles.
My car has an automatic transmission.

This is a common sign of a faulty coolant temperature relay. This is a relay that monitors the temperature of the coolant and relays this information back to the computer which then uses this information to make many different decisions regarding functions of the engine. When this sensor is not working properly, this may cause inaccurate readings to be supplied to the computer which causes a bit of a chain reaction in terms of the various other functions that are affected by this. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your coolant temperature sensor.

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