Posts Tagged: temperature gauge drops when driving

Temperature gauge drops when driving

Diagnose and fix temperature gauge drops when driving issue If your temperature gauge rises when idling but drops when driving, the cause is almost always a stuck open thermostat. The reason the temperature gauge drops when driving is because there’s much greater airflow through the radiator when you’re at speed than at idle. That increased airflow drops the temperature on the coolant coming into the engine. The job of the thermostat The thermostat is closed when you first start your engine. As the engine coolant heats up to around 150°F, … Read More