Engine Thermostat Failure

In the last month my PT Cruiser developed low coolant temperature on the temperature gauge .

The low temperature air from the car's heater gave a clue to the engine thermostat as the problem rather than a temperature guage sensor failure.

I wondered how the thermostat could fail a manner that would cause the cold coolant temperature (stuck open).

Turns out the frame that holds the whole valve assembly together failed such that the spring holding the valve closed became non-functional.

So nice to find the “smoking gun”.

The newly installed thermostat solved the problem perfectly.

Sweet.

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