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Old 10-06-2010, 02:59 AM   #10 (permalink)
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Originally Posted by Daox View Post
Allow me to answer your question with a question. How does an engine know how much fuel to inject? It calculates it based off the amount of air flowing into the engine. It knows the maximum amount of air it can let in (for the most part, there is compensation for air density etc so LOD isn't 100% exact), and it knows the minimum amount of air. Calculating percentage is a small step away then.
On my Diesel it will be a lookup value in a table based on factors like engine speed, temp, throttle position and air flow. But I still wonder how it knows what the max is to work out how much of it you are using.

To amplify a little. To work out % torque you would need to know for the current engine speed how much torque your engine can make at max, and then how much you are making now.

Or is it just fuel load, how much fuel is being added compared to how much could be added ?
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