How much can you improve your vehicle’s overall fuel efficiency by using a block heater?

• By 10%
  Explanation:

  "Using a block heater in cold weather can improve your vehicle’s overall fuel efficiency by up to 10%. A block heater warms the engine, reducing the energy needed to start and operate the vehicle in low temperatures, which helps save fuel and reduce emissions."
• By 20%
• By 30%
• By 40%