Diagnostic Information And Procedures - Suzuki GF60A Service Manual

IAC Valve Control Mode
Before started:
The IAC valve is initialized at a 70% opening position when engine is not running. (Ignition switch "OFF").
When cranking:
The IAC valve is controlled to operate at approx. 30 – 80% open position.
The open position changes depending on the cylinder temperature.
After start (fast-idle function):
The IAC valve is controlled to operate at approx. 40 – 80% open position until the timer, (set according to cylinder
temperature at cranking) expires. Then the open position gradually decreases until the engine rpm slows to the preset
idle speed.
When idling / trolling:
The IAC valve is controlled so that the engine speed is stable at the idling / trolling speed specified.
During this period, the IAC valve has an open position of approx. 0 – 30%, but will vary slightly as idling / trolling
conditions change.
When running (normal operation):
The IAC valve is controlled to operate at a 0 – 90% open position, dependent on current engine operating conditions.
When 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 idle / troll operating position to prevent engine stalling or
unstable running.
NOTE
Due to the limited intake air flow from the IAC passage, and in order to effectively use both the "Dash-
pot effect" and the "Fast-idle function", an IAC valve operating position of 0 – 30% at idling / trolling
speed is required.
Fuel Pressure Inspection
WARNING
!
Before starting the following procedure, be
sure to observe "Precautions on Fuel System
Service" (Page 1G-1) in order to reduce the
risk or fire and personal injury.
1) Relieve fuel pressure in fuel feed line.
Refer to "Fuel Pressure Relief Procedure" (Page 1G-
15).

Diagnostic Information and Procedures

ZAJ6111704001
2) Disconnect the high pressure fuel feed hose (1) from
the fuel delivery pipe upper union (2).
Loosen the delivery pipe upper plug (3).
1
Fuel System: 1G-11
3
2
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