If the engine overheats during long periods of idling but runs normally at highway speeds, the problem is most likely defective _____.
A)thermostat
B)water pump
C)cooling fan
D)radiator

Question

Quizplus · Accepted Answer

The cooling fan is responsible for pulling air through the radiator to cool the engine coolant when the vehicle is idling or moving slowly. If the engine overheats during idling but not at highway speeds (when air naturally flows through the radiator due to the vehicle's speed), it suggests the cooling fan may not be operating correctly to provide the necessary airflow for cooling.

If the Engine Overheats During Long Periods of Idling but Runs