With the continued rise in gas prices and cost of living, it would only make sense to pay particular attention to your car’s fuel consumption. It should be understood that a car with a large engine will use more fuel than a small four banger, and it would be foolish to expect the same consumption achieved by a smaller engine.
Keep in mind that your car still burns fuel even while idling (unless you drive a hybrid) and frequent exposure to traffic and stop and go conditions will cause you to burn more fuel. Fuel molecules are not fully combusted when an engine is in an idling state, and this will lead to early deterioration of engine parts. Air conditioning and extreme heat or cold will further aggravate the situation. Remember that a modern engine is more at home during highway driving and is subject to extreme stress when in idle. It should further be noted that no matter what the pundits say, your vehicle will register zero miles per gallon (MPG) when idling. This alone should deter you from unnecessary idling when using your car.
You can measure the actual consumption of your car even when idling, and this is achieved through the use of a laptop computer connected to the fuel injector of the car. The goal is to measure the pulse width of the fuel injector to measure the actual fuel consumption while idling. I Will Try.org will give you a better idea on how to properly measure fuel consumption while in idle.