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IAC Duty Cycle

Scan Tool Range 20% to 40%. The IAC Duty Cycle parameter indicates the opening of the idle air (bypass) passage of the IAC motor in a measurement of a percentage. The AC Duty Cycle percentage will increase when the PCM commands a larger idle air passage opening. The IAC Duty Cycle percentage will decrease when the IAC motor responds to a PCM command for a smaller idle air passage opening.