Q: My temperature gauge goes up and down when driving. We just recently changed the thermostat. It even does it when the ac is off. I

asked by on June 29, 2017

The temperature gauge in my car goes up and down. We recently changed the thermostat so I'm at a loss. It even does it when the ac is off, not sure if that matters or not
My car has a manual transmission.

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Hi there. It is quite possible that the electrical harness to the thermostat is faulty or you have an obstruction of coolant inside the radiator or cooling system that is causing an actual temperature flux as you are describing. It would probably be a good idea to have a professional mechanic complete a car is running hotter than normal inspection at your location, to determine the source of this problem - so the right repairs can be made.

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