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Q: After car is warm if I engage in park the heat will drop what causes that?

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When I turn the car on to warm up the temperature gauge doesn't warm up. It warms up enough to defrost the windshield is all. After car is warm if I engage into park the temperature will drop. What causes that?

My car has 130000 miles.
My car has an automatic transmission.

Hi there. The most likely cause for the engine temperature to drop in park, is the engine thermostat is stuck open, stuck open is better than stuck closed. The thermostat is designed to bring the engine up to and maintain operating temperature. This typically will occur within 5-10 minutes or a couple of miles of driving. Now days, the PCM (powertrain control module)/computer is capable of recognizing the engine not coming to and maintaining operating temperature. The PCM should in turn, set a check engine light. Proper diagnoses should be performed, to avoid unnecessary repairs. I recommend having your vehicle’s engine temperature drops in park be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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