|MadSci Network: Engineering|
Hi Stephen, I have been told (but have not verified it), that it takes 1/4-1/2 teaspoon of fuel to start a car engine (more if the engine is cold). As for idling, I can use my own car as an example. My car has a computer which measures instantaneous fuel consumption. Typically, it consumes 1.1 L/h. It's a 4-cylinder, '98 model, ie. fairly new, and fairly fuel efficient. Older cars, and cars with larger engines would probably use slightly more fuel. Also carburetted models tend to use more fuel than fuel injection models. So, at 1.1 L/h, 4 minutes of idling at the train track would use about 73 mL of fuel. Compared with the teaspoon or so used for starting, it would seem a lot more worthwhile switching your engine off. Hope this has helped, Jonathan Feldman University of Technology, Sydney
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