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Old 03-06-2012, 04:33 AM   #9 (permalink)
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I just thought that diesel injestion timing may be "measured" by a microphone attached to the injector. Since it'a a fully mechanical unit it should be pretty easy with an oscilloscope to find the point and timing for actual injection. As I remember diesel (old type) injectors are set up for constant fuel pressure, so what's changing is time. If you could actually measure the time of injection you can actually find an amount of injected fuel. Combining that with some kind of vehicle speed sensor will give you a full MPG. I think it can be done pretty easily. I could try to do that but don't have access to any old diesel engine and what worst I don't have oscilloscope to find characteristic points of the measured sound.

Gerhard Plattner: "The best attitude is to consider fuel saving a kind of sport. Everybody who has enough money for a strong car, can drive fast and hit the pedal. But saving fuel requires concentration, self-control and cleverness. It's a challenge with the nice effect of saving you money that you can use for other more important things."
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