Green stuff: Idling

Many municipalities now have anti-idling laws including Ottawa yet every morning I walk Dash, I see car after car parked in driveways "warming up". I know that they sit there for quite awhile most days because I don't walk him at the exact same time every day and the chances of their owners' slight variations in time and mine coinciding perfectly seems unlikely.

BUT - doesn't it use more gas to turn the car on and off than to leave it on? No! 10 seconds of idling can use more gas than turning it on and off.

BUT - isn't it good to warm up your engine? It warms it up a lot faster when driving it - your tires also need warmed up as do all moving parts...not just the engine. Even so, 30 seconds of idling TODAY (and it's freakin' cold out there) is enough. In fact, it uses MORE fuel in the first few minutes to warm the car up when it's that cold because the oil is thick and makes the engine work harder. Your block heater can resolve this (only plugged in for 2 hours and not overnight, preferably.

BUT - doesn't it wear on the car to restart it or to not warm up the engine? The costs of this have been approximated at $10/year...think about how much gas costs...you do the math.

BUT - I can't see out my windshield because of the frost yet even though I scraped my car off, isn't it dangerous to drive? YES...go for it, idle away until you have clear visibility.