2009-2010 Suzuki DF70A DF80A DF90A Outboard Service Manual, Page 194Get this manual
1G-11 Fuel System: IAC Valve Control Mode Before started: The IAC valve is initialized at 70 opening position when engine is not running(Ignition switch "OFF")When cranking: The IAC valve is controlled to operate at approx60 90 open positionThe open position changes depending on the cylinder temperatureAfter start (fast-idle function): The IAC valve is controlled to operate at approx60 90 open position until the timer, (set according to cylinder temperature at cranking) expiresThen the open position gradually decreases until the engine rpm slows to the preset idle speedWhen idlingtrolling: The IAC valve is controlled so that the engine speed is stable at the idlingtrolling speed specifiedDuring this period, the IAC valve has an open position of approx0 30, but will vary slightly as idlingtrolling conditions changeWhen running (normal operation): The IAC valve is controlled to operate at 90 open position, dependent on current engine operating conditionsWhen decelerating (dash-pot effect): When the throttle valve is suddenly returned to fully closed, and the throttle position sensor signal changes to "fully closed", the IAC valve is controlled to gradually return to an idletroll operating position to prevent engine stalling or unstable runningNOTE Due to the limited intake air flow from the IAC passage, and in order to effectively use both the "Dashpot effect" and the "Fast-idle function", an IAC valve operating position of 30 at idlingtrolling speed is required Diagnostic Information and Procedures