What are the risks of driving with a malfunctioning thermostat?

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What are the risks of driving with a malfunctioning thermostat?

A faulty thermostat can lead to engine overheating, increased emissions, poor fuel efficiency, and possible engine damage. Discussing these risks can help owners understand the importance of immediate repairs.

Sandeep asked on 13 Feb 2025 14:46:39 pm

1 Answer

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Car Mechanic Expert - on 13 Feb 2025 14:56:33 pm

A stuck thermostat can cause two main issues:

Stuck Open Thermostat: If the thermostat is stuck in the open position, it will prevent the engine from reaching its optimal operating temperature. This results in poor fuel economy and weak cabin heating since the engine is running too cool.
Stuck Closed Thermostat: If the thermostat is stuck closed, it will block coolant flow to the engine, causing it to overheat. This can lead to severe engine damage, including a blown head gasket.