The density of intake air varies with temperature. The colder the air, the denser it becomes. For this reason, a correction coefficient is used for changes in air temperature.
Referring to the coefficient graph, note that a standard air temperature of 68'F (20'C is used. At this temperature, the correction factor is 1.0.
For example, a correction factor of 1.0 means that no correction is made from the basic calculation. A coefficient of 1.1 means that injection duration is being increased by a factor of 10% while a coefficient of 0.9 means that injection duration is being decreased by a factor of 10%.
• As intake air temperature falls below the standard temperature, the correction coefficient increases and injection duration is increased (and vice versa).
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