What is the consequence of insufficient pressure in the cooling system?

• A. Boiling point decreases; coolant can boil at lower temperatures.
• B. Engine runs cooler than normal.
• C. Radiator becomes more efficient.
• D. The color of coolant changes.

Answer: (A)

Pressurizing the cooling system raises the coolant’s boiling point, letting it stay liquid at higher engine temperatures. If the pressure is insufficient, the coolant boils at a lower temperature, which can lead to overheating and loss of coolant through boil-off. This is why the consequence is that the boiling point decreases and the coolant can boil at lower temperatures. The other options don’t fit because running cooler is the opposite of what happens when coolant boils, radiator efficiency isn’t improved by low pressure, and coolant color isn’t affected by pressure.