What is the effect if thermostat valve is stuck?
What is the effect if thermostat valve is stuck? Thermostat stuck open: When the thermostat is stuck open, the engine temperature drops below normal when driving, especially on the highway in cold weather. A stuck-open thermostat can also cause lack of heat from the heating system. The Check Engine light may come on too. How do I know if my thermostat is stuck open or closed? If one (usually the top) is cooler, but the bottom is burning up, that indicates the thermostat is stuck closed as well. Do not stick your hand near the front of the engine while...